The classical three-body problem is traditionally characterized as analytically unsolvableand highly sensitive to initial conditions, despite being governed by deterministic equations ofmotion. Standard explanations attribute this behavior to nonlinearity and chaotic dynamicsarising from instantaneous pairwise force interactions. In this paper, the three-body problem isreexamined within the Theory of Imbalance of Energy (TIE), a framework in which interaction istreated as a dynamical process with internal temporal structure rather than as an instantaneousforce.Building on the extended least-action formulation introduced in earlier work, as well asthe emergence of memory, force, and inertia as effective reduced quantities, this paper arguesthat the three-body problem arises from a structural limitation of instantaneous force-basedreductions. When multiple bodies interact through dynamically evolving interaction imbalancewith finite redistribution times, reduced descriptions based solely on instantaneous configurationand velocity discard dynamically relevant state information.The purpose of this paper is not to provide an analytic solution to the three-body problem,nor to challenge the deterministic nature of classical mechanics. Instead, it offers a structuralexplanation for why exact long-term prediction fails generically in three-body systems. Theanalysis remains fully classical, deterministic, and causal, and does not invoke stochasticity,fundamental chaos, or modification of established physical laws.