Why do my points go down when I ask a question? Is the goal to lose all of your points?

Answer 1

They deduct 5 points for every question you ask. If you pick the winning answer you get 3 points. So asking a question is going to put you into negative points.

Answer 2

Right, and all you have to do to stay even is:

for every question you ask, choose a best answer AND answer someone else's question for 2 points.

It's to encourage feedback on answers and to encourage you to answer at least as many questions as you ask.