The cost of complexity usually appears after the excitement of adding it.

Complexity is exciting to add and expensive to keep. Another tool, another process, another feature, another commitment, each one reasonable at the moment of adoption and each one adding permanent friction that arrives long after the enthusiasm is gone. The cost is spread thin, which is exactly why it goes unnoticed.

Before adding a layer to anything, ask who will maintain it in a year, and whether the problem it solves is worth that. Where you can solve something by removing instead, do.