Ever built a feature for your biggest client that ended up alienating everyone else?

We once rushed out a custom workflow just to keep a whale account from churning. It made that one desk happy but completely cluttered the UI and confused our smaller self-serve users. Within a month we lost more MRR from the churned smaller accounts than that single big contract was even worth. Chasing the loudest voice in the room is a trap.

Have you ever caved to a massive customer request only to realize it broke the product experience for your core base?