You want to move teams. You’ve been doing the same job for three years. There’s an opening in another department. You’re qualified. You apply.
Your manager blocks it.
Not officially. Officially, they “need you where you are.” Officially, “this isn’t a good time.” Officially, they’ll “support your development goals” in a future quarter.
What they mean: you’re useful where you are and your leaving would be inconvenient for them. Your career growth is less important than their staffing problem.
The internal transfer system is a menu you’re allowed to look at but not order from.