Why am I just a "friend?"?

I’d like to know why I’m just a friend. I mean. I’m really nice to females. Very respectful. I don’t ask for naked pictures. I’m there for them when no one else is. So what else am I missing? A lot of my guy friends get girls all the time. Some of the females they’ve gotten are friends of mine who I used to like at one point, but somehow they get those girls easy. Aside from ethnic appearance. What do they have that I don’t? Why am I always labeled the “friend” or “best friend?”