"I can't keep track of all the policies" is I thing I hear regularly. Ignorance of the law is no defence, they say, but my attitude tends to be this:
Governance does nothing to change how things are. It just frames conversations.
If the policy says "when we do X, we do Y" and people are doing X but in a non-Y way - anyone who spots that should say "hey, I notice you doing X but not Y - but we have an agreement as a business via our governance to do X in a Y way - what's going on there?". That kind of thing.
You can set all the governance you want, but until people give each other feedback ("I was expecting you to do X and you didn't") - will anything change?