The complexity of the external environment exposes leaders and subordinates to situational disparities and information asymmetries, increasing the likelihood of emotional conflicts and unpredictable leader expressions. However, existing research has primarily focused on the effects of leaders’ predictable emotional expressions on subordinates, assuming that emotional cues align with situational information. In reality, emotional expressions do not always correspond with situational logic, making them appear unpredictable to observers. This study explores how leader emotional unpredictability shapes subordinates’ reactions. Grounded in the emotion-as-social-information (EASI) theory, we propose that leader emotional unpredictability heightens subordinates’ cognitive confusion and anxiety, subsequently influencing their interpersonal behavior and task performance. Furthermore, we expect these effects to be more pronounced in newer leader-subordinate relationships.

To test our hypotheses, we conducted three studies. A priori power analysis using G*Power indicated that a minimum sample size of 85 was required for the proposed model. Study 1 employed the critical incident method, collecting 427 valid responses. Participants were asked to recall and describe incidents in which they directly perceived leaders’ unpredictable emotional expressions, including the cause, process, and outcome of the event, before completing relevant questionnaires. Study 2 adopted a 2 (leader emotional predictability: predictable vs. unpredictable) × 2 (leader-subordinate relationship type: new vs. old) between-subjects experimental design. We obtained 248 valid samples via a professional online platform. Study 3 involved a two-wave field survey conducted one month apart among 386 leader-subordinate dyads from companies in the pharmaceutical, chemical, and food service industries. At Time 1, subordinates reported leaders’ emotional unpredictability, team procedural fairness, relationship length, and demographics. At Time 2, subordinates reported their anxiety, cognitive confusion, and interpersonal withdrawal, while leaders evaluated subordinates’ task performance.

Linear regression analyses and independent-samples t-tests were conducted to test Hypotheses 1 and 3, while the bootstrap method was employed to examine the mediating effects proposed in Hypotheses 2 and 4. In addition, simple slope analyses and ANOVA were used to assess the moderating role of relationship type in testing Hypotheses 5 and 6. The findings indicated that: (a) Leader emotional unpredictability was positively associated with subordinates’ cognitive confusion and anxiety; (b) Both cognitive confusion and anxiety mediated the relationship between leader emotional unpredictability and subordinates’ interpersonal withdrawal, whereas the indirect effect on task performance through anxiety was only supported in Studies 1 and 3; and (c) The type of leader-subordinate relationship moderated the indirect effects of leader emotional unpredictability via cognitive confusion on both withdrawal behavior and task performance. Specifically, in newer leader-subordinate relationships, the negative impact of leader emotional unpredictability on subordinates was most pronounced.

Our research makes several theoretical contributions. First, it extends the boundaries of the EASI framework by demonstrating how leader emotional unpredictability affects subordinates, providing a foundation for future studies that jointly consider emotional cues and situational information. Second, by uncovering the underlying dimensions of emotional unpredictability, the study enriches the theoretical understanding of complex leader emotional expressions and offers new insights into how such expressions relate to subordinate behavior in ambiguous contexts. Third, by introducing the mechanism of emotional complementarity, this research highlights how leaders’ unpredictable emotions can elicit complementary anxiety in subordinates, thereby expanding the conceptual scope of emotional complementarity within EASI. Finally, by examining the moderating role of leader-subordinate relationship type, our research takes a broader perspective on the interpersonal effects of leaders’ episodic emotional expressions, underscoring the critical role of relationship stage in emotion interpretation.