Definition

The accumulation of vendors in the operator’s stack without an audit process. The stack grows by addition and inertia, not by design, until it no longer reflects the operation’s actual needs.

Explanation

No operator sits down and decides to run twelve overlapping vendor tools. It happens one addition at a time — a new POS feature here, a marketing platform there, each one solving an immediate problem without anyone stepping back to ask what the whole stack looks like once it’s finished growing.

The cost of [Stack Drift] shows up later, and it compounds with [Stack Lock] — an unaudited stack tends toward vendor exit costs nobody accounted for, because nobody was tracking the stack as a whole while it grew. The fix isn’t refusing new tools, it’s running a periodic audit against actual need instead of letting the stack drift by default.