Why does the Predator not kill Arnold in the original movie, instead choosing to beat the snot out of him?

Question

I watched the movie and I know it has something to do with what he sees through the infa-red vision, but what is it, exactly? It makes little sense to me.

Answer 1

He wants to kill him but wants to do it in hand to hand combat as apposed to it's weapons. Just like you have seen in countless other films. However, it loses.  

Answer 2

If the predator kills Arnold in the movie then it would be meaningless for the audience as the hero dies so easily without a great fight with the predator, that's why.

Answer 3

I always thought it was what the predator COULDN'T see that saved his life.  Fear.  I'm guessing since the predator enjoyed the "hunt", he figured a creature that didn't fear him would be a worthy opponent.

It's been a while since I saw the movie though, but that was always my take on it.