Flour and water... at which temperature?
Pizza Dough is usually a yeast bread so you want your water to be warm (100-110F) to activate the yeast without killing it.

Quiche crust, like pie crust, develops the best texture when the flour is mixed with the butter (or shortening) in a solid state, so you want to add other liquids at a cool temperature to prevent melting the butter to a liquid and creating a less flaky crust. 

I am not really sure about tortillas, but with the first two examples you can see that temperature is important and differs from application to application.