Running one model is rarely enough for production. We stack models because they...

https://wiki-dale.win/index.php/The_Architect%E2%80%99s_Guide_to_Taming_Multi-Model_Sprawl

Running one model is rarely enough for production. We stack models because they fail in different ways and bring different strengths to the table. Routing requests lets us pick the right tool for the task, but do not get lazy