leave well alone
US /liːv wɛl əˈloʊn/
UK /liːv wɛl əˈloʊn/

1.
가만히 두다, 건드리지 않다
to not try to change something that is already satisfactory or working well, because doing so might make it worse
:
•
The system is working fine, so it's best to leave well alone.
시스템이 잘 작동하고 있으니 가만히 두는 것이 최선이다.
•
I was going to redecorate, but my husband told me to leave well alone.
다시 꾸미려고 했는데, 남편이 가만히 두라고 했다.