the tail wagging the dog

US /ðə teɪl ˈwæɡɪŋ ðə dɔɡ/
UK /ðə teɪl ˈwæɡɪŋ ðə dɔɡ/
"the tail wagging the dog" picture
1.

本末倒置, 喧宾夺主

a situation in which a small or less important part of something controls or dominates the whole thing

:
Allowing a minor issue to dictate the entire project budget is a classic case of the tail wagging the dog.
让一个小问题决定整个项目预算是典型的本末倒置
In this company, it often feels like the tail is wagging the dog, with junior staff making decisions for senior management.
在这家公司,常常感觉是本末倒置,初级员工为高级管理层做决策。