Why don't Aliens wear clothes?

Answer 1

That's a question for the artists who create them. It's one thing to devise what an alien creature might look like, it takes a little extra imagination to design a suitable wardrobe.

Then there is the slime factor and the logistics behind that. Many of the aliens are depicted as slimy. It is hard to be covered with slime and hygienically wear clothes. Plus what if the slime dries out? Then any clothes would be glued to them.