In today's globalizing economy, the organizational environment has become markedly more demanding. Firms operating across industries face mounting competitive pressures that compel them to continually improve their operational efficiency and workforce quality. In this context, employee performance has emerged as a central concern for managers, human resource professionals, and organizational scholars (Mathis & Jackson, 2016). High-performing employees are widely recognized as a critical source of competitive advantage, particularly in service-intensive industries, where the quality of human capital directly shapes customer and organizational outcomes.
Indonesia's corporate sector has not been immune to these dynamics. As the country's economy continues to integrate with regional and global value chains, Indonesian firms face growing pressure to raise productivity while managing the psychosocial demands placed on their workforces. Job stress and work motivation are two variables that have been recurrently identified in the organizational behavior literature as significant antecedents of employee performance. Job stress arises when employees perceive work demands as exceeding their coping resources, producing physiological, psychological, and behavioral responses that can diminish the quality and quantity of their work output (Lazarus, 1999; Robbins & Judge, 2012). In contrast, work motivation refers to the internal and external forces that energize, direct, and sustain goal-directed behavior in the workplace (Luthans, 2006; Deci & Ryan, 2000).
Although both constructs have been extensively studied in Western and East Asian organizational contexts, Indonesian literature on their combined influence on employee performance remains comparatively sparse, particularly at the single-firm, employee-level analysis level. This is noteworthy because Indonesian workplaces differ from those studied in many prior investigations in terms of organizational culture, leadership norms, and legal and institutional frameworks within which employment relationships are embedded. Moreover, small-to-medium enterprises in Indonesia often lack the formal human resource infrastructure that might buffer employees from stress or sustain motivational practices. Therefore, understanding how job stress and work motivation jointly and separately predict performance in such contexts is both theoretically and practically significant.
The present study was conducted at PT. XYZ, a private company based in Jakarta, used a sample of 30 permanent employees. This study addresses two specific research questions: (1) Does job stress significantly influence employee performance at PT. XYZ? and (2) Does work motivation significantly influence employee performance at PT. XYZ? The findings contribute to the growing Indonesian empirical literature on organizational behavior and offer actionable insights for human resource practitioners seeking to optimize employee output through targeted motivational and stress management interventions.

2.1. Employee Performance
Employee performance is a foundational concept in organizational behavior and Human Resource Management (HRM). It refers to the work outcomes achieved by an individual or group within an organization during a specified period, evaluated against predetermined standards of quality, quantity, timeliness, and behavioral appropriateness (Mangkuprawira & Hubeis, 2007; Soeprihanto, 2009). Performance is not a unidimensional construct; rather, it encompasses task, contextual, and adaptive performance dimensions that together capture the breadth of employees' contributions to organizational goals (Bakker & de Vries, 2021).
Several theoretical perspectives have been proposed to explain the determinants of employee performance. Motivation-ability models propose that performance is a joint function of employee capability and the effort employees are willing to exert (Hersey & Blanchard, 1993). Resource-based views highlight the role of human, social, and psychological capital in enabling consistent high performance over time (Hobfoll et al., 2018). Recently, the job demands-resources (JD-R) model has gained prominence as an integrative framework linking work environment characteristics, both demands and resources, to performance outcomes through motivational and strain pathways (Schaufeli & Taris, 2023). Performance assessment typically encompasses six core dimensions: quality of work output, quantity of output, timeliness, effectiveness, autonomy, and interpersonal cooperation (Robbins, 2006; Kasmir, 2016).
In the Indonesian context, employee performance has attracted growing research attention in both public and private sector organizations. The combination of hierarchical organizational cultures, collectivist social norms, and a rapidly evolving regulatory environment creates distinctive conditions under which motivation and stress operate in the nursing profession. Studies in Indonesian settings have consistently found that relational factors, leadership quality, and organizational support moderate the relationship between individual characteristics and performance outcomes.

2.2. Job Stress
Job stress is defined as an individual's psychological and physiological response to perceived work demands that exceed the available coping resources (Robbins & Judge, 2012; Lazarus, 1999). It encompasses three primary symptom clusters: physiological symptoms, including cardiovascular responses, headaches, and metabolic changes; psychological symptoms, including anxiety, irritability, tension, and depressed mood; and behavioral symptoms, including reduced productivity, increased absenteeism, and dysfunctional coping behaviors, such as substance use (Luthans, 2011; Robbins & Judge, 2012).
Key organizational stressors identified in the literature include role ambiguity, role conflict, physical work factors, adverse working environments, insufficient social support, limited decision latitude, threats of physical harm, and excessive responsibilities. In the JD-R model, job demands are conceptualized as physical, psychological, social, or organizational aspects of the job that require sustained effort and are, therefore, associated with physiological and psychological costs (Schaufeli & Taris, 2023). When demands persistently outpace available resources, a strain pathway is activated that ultimately impairs performance and well-being (Bakker & de Vries, 2021).
The relationship between job stress and employee performance is generally negative; however, the magnitude and direction of this relationship are moderated by individual characteristics, organizational support, and the nature of the tasks involved. Some research suggests an inverted-U relationship, where moderate stress can enhance alertness and performance, while chronic or acute high stress is consistently associated with performance impairment. Based on this theoretical and empirical foundation, the following hypothesis is proposed:
H1: Job stress has a significant negative effect on employee performance at PT. XYZ.

2.3. Work Motivation
Work motivation is defined as a constellation of internal and external forces that initiate, direct, sustain, and regulate efforts toward work-related goals (Luthans, 2006; Gagné & Deci, 2022). From a self-determination theory perspective, motivation exists on a continuum from extrinsic regulation, in which behavior is driven purely by external contingencies, to intrinsic motivation, in which behavior is enacted for the inherent satisfaction it produces (Deci & Ryan, 2000; Howard et al., 2021). More autonomous forms of motivation, whether intrinsic or well-internalized extrinsic, are associated with deeper engagement, higher quality performance, and greater persistence in the face of difficulty (Howard et al., 2021; Gagné & Deci, 2022).
In Herzberg's two-factor theory, motivational factors originate from the content of work itself, encompassing achievement, recognition, responsibility, growth, and the intrinsic character of tasks, while hygiene factors, including working conditions, interpersonal relationships, and job security, prevent dissatisfaction without directly stimulating motivation (Herzberg, 1966). The distinction between intrinsic and extrinsic motivation is important because organizations that rely exclusively on extrinsic rewards may undermine intrinsic motivation over time, whereas those that cultivate autonomy-supportive leadership, meaningful task design, and developmental feedback tend to sustain higher levels of discretionary effort and performance quality.
In the Indonesian organizational context, work motivation is shaped by a combination of individual aspirations, group dynamics, leadership styles, and organizational culture. Research has consistently demonstrated that motivated employees are more likely to comply with organizational standards, exercise initiative, and sustain performance during demanding periods. Based on this evidence, the second hypothesis is proposed as follows:
H2: Work motivation has a significant positive effect on employee performance at PT. XYZ.

2.4. Combined Prediction of Employee Performance
While job stress and work motivation are theoretically and empirically linked to employee performance through distinct pathways, their simultaneous examination within a single model is analytically more informative than separate bivariate analyses. In practice, job stress and motivation interact: high stress may erode motivational resources through depletion mechanisms proposed by the conservation of resources theory (Hobfoll et al., 2018), while high motivation may buffer the performance-impairing effects of stress by sustaining engagement and goal commitment (Bakker & de Vries, 2021). Accordingly, the third hypothesis is as follows:
H3: Job stress and work motivation jointly have a significant effect on employee performance at PT. XYZ.

3.1. Research Design and Setting
This study employed a quantitative, cross-sectional, explanatory research design in which multiple linear regression was used to examine the simultaneous and partial effects of job stress and work motivation on the performance of employees. This research was conducted at PT. XYZ is a private company based in Jakarta, Indonesia. The decision to focus on a single organization allowed for the control of organizational-level confounds that might otherwise complicate inferences about employee-level processes in the study.

3.2. Population and Sample
The study population comprised all 52 permanent employees of PT. XYZ. Given the small and bounded population, a total sampling (saturation sampling) strategy was adopted, meaning that all population members were invited to participate (Sugiyono, 2017). Questionnaires were distributed to all 52 employees; however, after excluding incomplete returns, 30 questionnaires were retained for the analysis. This response rate, while representing a subset of the total population, is consistent with practices in similar single-firm organizational studies and provides sufficient statistical power for the regression model employed.

3.3. Measures
All three constructs, employee performance, work motivation, and job stress, were operationalized using multi-item Likert-scale questionnaires with response options ranging from 1 (strongly disagree) to 5 (strongly agree). Employee performance (Y) was assessed using three items capturing the quality, quantity, and timeliness of work output, consistent with established performance indicator frameworks (Robbins, 2006; Kasmir, 2016). Work motivation (X1) was measured using three items reflecting an employee's willingness to exert effort, sustain goal direction, and integrate personal needs with organizational expectations. Job stress (X2) was assessed using three items capturing the experienced tension, pressure, and physiological and psychological strain in the workplace (Greenberg, 2015).

3.4. Data Analysis
Data were analyzed using the IBM SPSS Statistics software. The analytical procedure comprised four stages as follows. First, validity was assessed using Pearson’s bivariate item-total correlations, with items regarded as valid if the corrected item-total correlation exceeded the critical r-value for the sample size and significance level (r-table = 0.31 for n = 30, α = 0.05). Second, reliability was assessed using Cronbach's alpha, with values exceeding 0.70 considered acceptable (Sholihin & Ratmono, 2013). Third, classical assumption tests were conducted, including normality (one-sample Shapiro–Wilk), multicollinearity (tolerance and VIF), and heteroscedasticity (Spearman's rho correlation of independent variables with unstandardized residuals). Fourth, multiple linear regression was performed to estimate the unique and joint contributions of job stress and work motivation to employee performance. The significance of the individual predictors was evaluated using t-tests (α = 0.05), and the significance of the full model was evaluated using the F-test.

4.1. Validity and Reliability Tests
All items across the three constructs demonstrated corrected item-total correlations exceeding the critical r-value of 0.31, confirming construct validity. For employee performance, item correlations ranged from r = 0.405 to r = 0.638; for work motivation, from r = 0.591 to r = 0.690; and for job stress, from r = 0.461 to r = 0.587, respectively. The results are summarized in Table 1.

Table 1. Validity Test Results for All Variables

Note: n = 30; r-table (α = 0.05, df = 28) = 0.31.

Reliability analysis using Cronbach's alpha yielded acceptable internal consistency for all three constructs: employee performance (α = 0.701), work motivation (α = 0.793), and job stress (α = 0.707). All values exceeded the conventional threshold of 0.70, confirming the instrument’s reliability (see Table 2).

Table 2. Reliability Test Results for All Variables

Note: Threshold: α > 0.70 (Sholihin & Ratmono, 2013)

4.2. Classical Assumption Tests
The Shapiro-Wilk test for the normality of residuals returned a significance value of 0.827, which substantially exceeded the 0.05 threshold, confirming that the residuals were normally distributed (H0 accepted). The multicollinearity test revealed tolerance values of 0.704 (VIF = 1.420) for both work motivation and job stress, well within the acceptable ranges (tolerance > 0.10; VIF < 10), indicating no multicollinearity. The heteroscedasticity test using Spearman's rho correlation produced significance values of 0.682 (work motivation) and 0.876 (job stress) for the correlation with unstandardized residuals, both exceeding 0.05, thus confirming the absence of heteroscedasticity. Together, these diagnostics confirm that the assumptions of multiple linear regressions were satisfied.

4.3. Multiple Linear Regression Analysis
Table 3 presents the results of multiple linear regression analysis. The model explained 50.1% of the variance in employee performance (R² = 0.501, Adjusted R² = 0.464), and the overall model was statistically significant (F (2, 27) = 13.539, p < 0.001), supporting H3. The regression equation is as follows:

Y = 2.033 + 0.407X₁ + 0.138X₂

where Y = employee performance, X₁ = work motivation, and X₂ = job stress.

Table 3. Multiple Linear Regression Results

Note: R² = 0.501; Adjusted R² = 0.464; F (2, 27) = 13.539, p < .001. n = 30.

At the partial level, work motivation was a statistically significant positive predictor of employee performance (B = 0.407, β = 0.577, t = 3.564, p = 0.001), thus supporting H2. This indicates that, when job stress is held constant, a one-unit increase in work motivation is associated with a 0.407-unit increase in employee performance. However, job stress did not produce a statistically significant partial effect (B = 0.138, β = 0.202, t = 1.245, p = 0.224), meaning that H1, which predicted a significant negative partial effect, was not supported. These results are discussed in detail in Section 4.4 of this paper.

4.4. Discussion

4.4.1. The Role of Work Motivation
The finding that work motivation significantly and positively predicts employee performance is consistent with a broad and robust body of empirical evidence (Howard et al., 2021; Gagné & Deci, 2022). In the JD-R model framework, work motivation functions as a key motivational pathway through which job resources, such as supportive leadership, skill variety, and feedback, are translated into higher performance (Bakker & de Vries, 2021). In the PT. In the XYZ context, the relatively strong standardized coefficient (β = 0.577) indicates that motivational processes account for a substantial portion of the explained variance in performance, underscoring the organization's need to invest in practices that sustain and enhance employee motivation. These may include goal-setting interventions, recognition systems, developmental opportunities, and leadership practices that emphasize autonomy support and constructive feedback.

4.4.2. The Partial Non-Significance of Job Stress
The non-significant partial effect of job stress on employee performance (t = 1.245, p = 0.224) was noteworthy. One explanation lies in the relatively small and homogeneous sample drawn from a single organization, which may have limited the statistical power needed to detect a stress-performance relationship of modest effect size. Alternatively, the absence of a significant partial relationship may reflect a genuine empirical pattern in which job stress exerts its influence on performance primarily through interactions with motivational and relational variables rather than independently of them. In the presence of high work motivation, employees may effectively buffer the performance-impairing potential of stress through volitional coping strategies, as proposed by the conservation of resources theory (Hobfoll et al., 2018). However, the simultaneous F-test result confirms that when job stress and work motivation are considered together, their joint contribution to performance is statistically significant (F = 13.539, p < 0.001), which is consistent with H3 and aligns with findings on the interactive dynamics of demands and resources in workplace performance models.
The practical implication is that organizations should not regard job stress as inconsequential simply because its independent partial effect may vary across settings. Sustained or escalating stress loads can erode motivational resources over time, resulting in cumulative impairment of performance. PT. XYZ would benefit from periodic stress assessments, workload management reviews, and the implementation of employee assistance programs that address both the sources of job demands and the resources available to employees to cope with them.

4.4.3. Limitations
This study has several limitations that should be acknowledged. First, the sample of 30 employees from a single organization limits the statistical power and generalizability of the findings. Second, the cross-sectional design precludes causal inference; longitudinal or experimental designs are needed to establish the directionality of the relationships observed. Third, all data were collected through self-reported questionnaires, which introduced the possibility of common method bias. Fourth, although the three-item scales demonstrated acceptable reliability, they were relatively brief and may not fully capture the multidimensionality of each construct. Future research should use larger samples, multi-source data, and more comprehensive measurement instruments to produce robust and generalizable findings.

This study examined the partial and simultaneous effects of job stress and work motivation on employee performance at PT. XYZ, Jakarta, Indonesia. Using multiple linear regression on data from 30 permanent employees, the results demonstrate that work motivation is a significant positive partial predictor of employee performance (t = 3.564, p = 0.001), whereas job stress does not produce a statistically significant partial effect (t = 1.245, p = 0.224). Nevertheless, both variables jointly exerted a significant influence on performance (F = 13.539, p < 0.001), explaining 50.1% of the variance in the dependent variable.
These findings have important practical implications for human resource management. Organizations seeking to enhance employee performance should prioritize the development of motivational climates, characterized by clear goal-setting, meaningful recognition, autonomy-supportive leadership, and developmental opportunities, while simultaneously monitoring and managing job stress levels to prevent long-term erosion of motivational resources. Future research should expand the sample scope, incorporate longitudinal designs, and examine the mediating and moderating variables through which job stress and work motivation interact to shape performance outcomes across diverse organizational contexts in Indonesia.