In the end, as a leader, you are always going to get a combination of two things: what you create and what you allow.
Don't use all-or-nothing thinking. Take each day as its own day, and don't worry about it if you mess up one day. The most important thing you can do is just get back up on the horse.
A culture is like an immune system. It operates through the laws of systems, just like a body. If a body has an infection, the immune system deals with it. Similarly, a group enforces its norms, either actively or passively.