If it ain’t broke, don’t fix it
Definition 1 of 1
Pro Tip 1/3Usage Context
Mostly used in informal contexts or casual conversations, not in formal writing. 
This old car still runs great, so if it ain’t broke, don’t fix it.
Pro Tip 2/3Conservatism
The phrase can imply a conservative approach to improvement or change, suggesting caution. 
We've always done it this way; if it ain’t broke, don’t fix it.
Pro Tip 3/3Not Literal
It's a metaphorical phrase; 'broke' doesn't only refer to physical objects but to systems and methods. 
Our weekly meeting format works well; if it ain’t broke, don’t fix it.