"Complexity is rarely created deliberately; it accumulates.
Most disasters begin as a reasonable exception. In a migration that looks reversible until the data moves, the system learns the exception faster than it learns the risk.
In a migration that looks reversible until the data moves, the shortcut will be framed as temporary. Temporary decisions have a way of turning into the operating mode, especially when they make next week easier. You see it in a cache added for speed that quietly changes correctness semantics. Clarity is not certainty; it is a small commitment the team can execute without reopening the decision at every update.
Grady Booch is a reminder to audit the argument, not the intention. Write the failure story forward while the decision is still reversible, then insist on one guardrail. End with one move, not three.