Previous papers in the Theory of Imbalance of Energy (TIE) established the necessity of aphysical substrate with finite propagation and delayed corrective influence, and demonstratedthat gravity emerges as organized motion driven by resistance gradients within that substrate.The present work addresses a distinct and unresolved dynamical phenomenon: resistance tochanges in motion, commonly identified as inertia.This paper shows that inertia is not a fundamental property of matter, nor a consequenceof gravitational behavior. Instead, inertial resistance arises necessarily when coherent boundeddomains are subjected to imposed reconfiguration within a substrate that cannot update instantaneously. Acceleration corresponds to forcing a mismatch between imposed change anddelayed corrective response, and resistance emerges from this mismatch rather than from intrinsic mass or force. The analysis establishes inertia as a relational and unavoidable consequenceof persistence under temporal constraint, completing the minimal dynamical foundation of theTIE framework while deliberately deferring quantitative laws, constants, and mass definitionsto later stages.