When a leader cuts one corner, the whole team learns the shortcut.

Standards are set by behavior at the top, not by what gets said in a meeting. Everyone watches what the person in charge tolerates in themselves, and that becomes the real floor whatever the stated rule says. One visible exception does more than a season of reminders, because it proves the rule is optional.

If you are leading anything, even informally, do the tedious part where people can see you do it. When you have to cut something, say out loud that you are cutting it and why. Naming it stops it becoming the new standard.