You need to have standards for yourself to live up to. Though as a leader, the standards you bring with you often become the standards of the team you lead. You cannot hold a team to higher standards than you have for yourself.
Once you joined the team, you lived at a certain standard that I played the game. I would not take anything less. One thing about Michael Jordan is that he never asked anyone to do anything that he didn’t do.Michael Jordan
If not everybody can meet a standard (including yourself), the easy way out is to set a lower standard. This will also happen when you decide not to do anything. Since a bar is something you set, also something you accept.
When it comes to standards, as a leader, it’s not what you preach, it’s what you tolerate.Jocko Willink
Your job is to lift people towards the standard you want to meet. Since if they are not able to meet it yet, it is your job to get them there. Leading by example is one thing, though actively working with them to bridge the gap is essential to get them there.
One essential part of setting standards is being humble enough to accept that you also have your imperfections and need to work just as hard as anybody else in your team to meet the standards you expect (or to discover your standards were not meeting reality, and you might want to reconsider).
When you are transparent about this, you can create an environment that allows you to increase the standards of everybody in the team, including those yourself.
Do not settle for less. Strive for more.