No more commitment?

I asked him "what are your intentions with us?" He said "where do you this going?" So I told him I see us together but idk if that's what he wants. We decided to talk about this in person but it so happens that the next 3 days, I didn't see him and then one day I stopped hearing from him. I had called; texted; and sent a msg on social media. No reply. He's alive and well (as per a friend of ours) but why do some men run away at the topic of relationship??