In a training I was asked “How long do you need a Scrum Master?”
Let’s just think about FC Bayern München. The well known soccer club.
They definitely play world class soccer.
What’s your best guess:
do they still have a trainer, do they have a coach?
Yes, they do.
Although they know the rules of soccer.
Although they know who plays which position.
The coach does not explain the rules to them. The coach observes them and shares and reflects those observations with them. Like a mirror, sharing an outside perspective. And this is what they learn from and become better, better at soccer and better as a team.
As an organization you can decide:
which league do you want to play? How much are you willing to invest for that?
It’s important that you take an informed decision here as it will influence your business. And the league you are playing.