Workforce flexibility – discretion over when, where, and how work is performed – has become a central rather than peripheral determinant of the employment relationship, accelerated by post-pandemic hybrid-work norms. Yet the literature linking flexibility to employee satisfaction is theoretically fragmented: autonomy-, resource-, and boundary-based explanations are each tested in isolation, and a growing critical literature documents a “flexibility paradox” in which flexibility produces self-exploitation and diminished thriving rather than satisfaction. This conceptual paper integrates Job Demands–Resources (JD-R) theory, Self-Determination Theory (SDT), and Work/Family Border Theory into a single moderated-mediation framework in which workforce flexibility influences employee satisfaction through three parallel mechanisms – perceived autonomy, job resource adequacy, and work-nonwork boundary congruence – while flexibility stigma and supervisor support act as boundary conditions determining whether flexibility is enabling or exploitative. Drawing on a thematic synthesis of the literature and a structured gap analysis, the paper develops seven theory-derived propositions and an empirical validation agenda using PLS-SEM. It contributes theoretically by reframing contradictory flexibility-satisfaction findings as a moderated-mediation phenomenon rather than an empirical inconsistency, and practically by identifying the organisational conditions under which flexibility policies succeed or backfire.