Why do so many great leaders struggle when they get promoted?

Because the very thing that earned them the promotion is often the thing they now have to stop doing.

I see this all the time.

Almost every leader I work with is somewhere on the same arc.

It starts with competence.
Getting good at the work itself.

Then comes a harder shift.
Leading the people who do the work.

This is where your old strengths can quietly turn into liabilities.

And then, if you keep climbing, a third shift.
Leading other leaders.

Here almost nothing is yours to do directly.
And everything depends on the conditions you set.

Here's the thing:
Each stage asks you to let go of what made the last one work.

Which is why growing as a leader is mostly subtraction.

The hard part isn't deciding what to take on.
It's figuring out what to put down.