I read in a magazine back in the 90s that best practices were just process karaoke. I think there's a lot of fake best practice parading itself around in the world made up by self-perpetuating committees. Who decides that one way is best? Best for who? Just because they say so?
I've also seen real best practices misused utterly to remove any room for professional judgment or flexibility. Best practices aren't a recipe for jello. They're only best practices until they aren't.