Should I be satisfied with what I have with girls?

Ok well I get a lot of girls in total from the year of 2010 and 2011 i have gotten at least 15 girls or so. not in the sense of relationship but all like intense flirting. The thing is I haven't been in a relationship for years. I'm not really complaining though because like i always have a girl in my arms but in the end we always stay in that friend zone. Its not because im too nice a guy though or because they think im gay but.. Well i honestly don't know why, but there are specifically 2 girls i really like and i might ask one of them out but im not sure. Also one thing i wanna make clear im no player. but seince im not tied down to any girl i flirt very much and they flirt back. but sometimes i wonder why girls never wanna go further like most of the girls i have flirted with, we have gotten soo far its like why not be in a relationship. i dont know i just wanna know why. im happy that i at least have girls and stuff but i kinda want something more but it feels like they think im not relationship material. But i for sure am i guess im just a clown sometimes but they know i can be serious and mature. Advice or Suggestions.. thanks!