Sometimes its useful to see stats of buildings with garrisoned units - Say I was trying to see how much attack an enemy castle has.
But if it has units garrisoned inside, it’s stats are not visible on the UI.
See here - I want to see how much hp the mosque has left. I cannot. Instead I can see that it has 3 scholars garrisoned inside. This is actually NONE of my business, it’s the enemy’s business. I should not be able to see this.