Yes. Trust me on this one. You're filling the crust with a very wet, very heavy filling, so it truly needs to be pre-baked (also called blind baking) before filling. If you do not full pre-bake your crust, you will most likely end up with a soggy quiche bottom, which, fellow fans of the Great British Bake-Off will know, is one of the worst things that can happen to a pastry crust!