I can't curb my curious to not asking this silly question any longer lol! After watching many auto repair memes where bad part with leaky gasket ruined everything, or customer sealed oil pan like a monster but still leaking nevertheless. So why can't car manufactures design a round-shape water pump or oil pan that can spin-on, with hand tight torque requirement, and rubber O-ring preinstalled? Now we reduce the cost for bolts, expensive metal gaskets, power tools and users have less chance to do the job wrong.