Why can't NTs ever answer a straightforward question with a straightforward answer?

God, it's like getting blood out of a stone sometimes!

Usually what happens is, I'm having a conversation, one of them says something confusing. I ask what they mean and they either ask another question, or make fun of me, or stare blankly. The more I ask for clarification, the weirder they get. It's like they're playing a game.

So I usually just give up and shut up.

Why is it so frigging difficult to answer a straightforward question??