Momentum Bias

Momentum Bias is the tendency to continue a course of action primarily because it's already in motion — not because ongoing evidence supports it. Once energy, resources, and identity have been invested in a direction, the psychological cost of stopping exceeds the logical cost of continuing, even when the original rationale has evaporated. In physics, momentum is neutral; in psychology, it's a trap. Founders keep scaling a failing product because the team is already built. Investors keep doubling down because they've already committed capital. Executives keep pursuing an acquisition because the process has gone too far to stop. Momentum Bias is distinct from Sunk Cost Fallacy in emphasis: sunk cost focuses on past investment; momentum bias focuses on the feeling that motion equals progress. The most dangerous form is when momentum is mistaken for validation.

Institute regular "zero-based" reviews where every continuing initiative must re-justify itself as if it were being proposed fresh. Remove the implicit advantage that existing projects have over new proposals. Ask: if we weren't already doing this, would we start it today given what we now know? If the answer is no, momentum — not merit — is keeping it alive.

Momentum Bias is the tendency to continue a course of action because it's already in motion, mistaking movement for progress. In business, it keeps failing products alive, sustains bad strategies, and prevents necessary pivots. Counter it with zero-based reviews that force every initiative to re-justify itself as if it were being proposed for the first time.