All shipped software carries debt. The question is whether the debt is localized, understood, and priced into velocity.
Refactor when change cost is accelerating—every feature touches the same god module, bugs cluster in one area, or onboarding takes weeks.
Contain with seams when you need speed: feature flags, adapter layers, and module boundaries let you replace internals later.
Pay down debt as part of features that already require touching the area. Opportunistic cleanup beats “refactor quarters” that never ship.
