What does the mobile checkbox under the Armory Props tab do?

I’ve just noticed this checkbox, when hoovering over it it says ‘‘Object moves during gameplay’’.
I’ve been using mobile objects all this time and never checked the box, what difference does it make? Is it for optimization?

Not really sure what that check does, but

Is it for optimization?

my guess is that probably it has something to do with baking lights or shadows or others (a feature I haven’t used myself). In other engines sometimes you have to explicitly tell the engine what objects move or remain static in the scene to take into account only the static ones when baking.