Okay we can reference hard nose coaches that have been successful and ones that have failed.
Here is the more challenging question: Can you name one successful head coach that allowed his players to be late for team meetings and/or didn't give a shit about disciline?
Tom Flores, former Raiders coach. From what I've heard, he was pretty lax on discipline. While he did impose curfews and expect his guys to be on time for meetings, he didn't make a big deal on guys who were late, and was pretty lenient on missing curfews. His players partied at all hours of the night when they were in town for their two Super Bowls that he coached. And he won those two Super Bowls.