when cooking quiche, why is the pastry precooked?

To keep the egg from soaking in.

The reason for the beans is to keep the pastry from rising,but the reason the pastry is pre cooked is becuase eggs don't take long to cook and if you put wet eggs on raw wet pastry you will have done eggs, gooey pastry and a yucky dinner.

by baking the pastry for 10 mins. first it stops your quiche mixture making the base soggy and stopping it from cooking properly.

The beans or rice prevent the pastry from rising.

The term is 'blind baking'.

the reason for the rice or beans is to keep the crust from puffing up while baking. it's just a weight. the reason for precooking the crust is probably either the time allowed in the recipe isn't enough to cook it, or just to keep it from turning out soggy.

It cooks the pastry base and stops it from rising up.

to keep the quiche from getting soggy and to keep it moist

so the pastry does not get soggy