Task idiosyncratic deals and task interdependence: Effects on demand–ability fit and employee outcomes

Abstract Task idiosyncratic deals (I‐deals) exemplify an employer and employee co‐creating job design approach. However, past literature has predominantly relied on social exchange mechanisms to explain their impact on employee behaviour, which may be insufficient in capturing the critical job‐related mechanisms underlying the effects of task I‐deals. We draw on person–environment (PE) fit theory to propose that demand–ability (DA) fit can enrich our understanding of the effect of task I‐deals on employee behaviour. To test this mechanism, we conducted two studies. One was a field survey collected from 468 employees and 107 supervisors across three time points. The other was a pre‐registered scenario‐based online experiment involving 400 full‐time employees. Through these two studies, we found that task I‐deals were positively related to job performance and voice behaviour, and DA fit mediated these positive relationships. In addition, task interdependence enhanced the positive effect of task I‐deals on DA fit. The overall moderated mediation model was also significant. These findings highlight the importance of task I‐deals as an alternative approach to job design beyond top‐down and bottom‐up job design approaches and underscore PE fit as a novel theoretical perspective for understanding the impact of task I‐deals.