Why does my crush talk more when were alone, then when there are people around. Like when were at the gym...?

When were at the gym, we see each other sometimes. You noticed that when there are other peple around doing weights or what not, he doesn't talk to me, or barley acknowledge me, but when no one or minimal people are around he comes up to me and talks to me. Its confusing why he does this.
Why does my crush talk more when were alone, then when there are people around. Like when were at the gym...?
Post Opinion