There's no fixed interval where a brand quietly expires. Companies rebrand every eighteen months out of boredom and others run the same identity for two decades without issue. The trigger isn't time. It's whether the identity still matches the business.
A handful of situations genuinely call for a rebrand: the business has fundamentally changed what it sells or who it sells to, the identity is actively working against how the market perceives you, or internal teams have quietly stopped using the brand guidelines because they don't fit anymore.
Wanting a refresh because leadership is tired of looking at the same logo is real, but it's not the same problem as a broken brand. Boredom is solved with a lighter touch: refined typography, an updated colour application, tightened guidelines. It rarely needs a ground-up rebuild.
Every rebrand resets recognition to zero. Customers who've built a mental shortcut for your old mark have to relearn a new one, and that recognition is worth real money. Rebrand too frequently and you're paying that cost repeatedly without ever banking the payoff.
Ask whether the problem is the identity itself, or how consistently it's being applied. A brand that's never been used consistently often looks broken when the real issue is discipline, not design. Fix the discipline first. If the identity still doesn't fit after that, then it's time.