Why do guys not message back on tinder????

So, I recently got tinder after starting college to get to know people and I've got a couple dozen matches so far. I've messaged three of them and shocker: NONE of them messaged me back? I'm not being creepy or anything. I just say "hi" and maybe ask them a question about something in their bio or in a picture. What am I doing to cause this? Its like, why did you swipe right if you weren't gonna talk? Ugh. It's lowering my self esteem. Can anyone explain why this is happening?