Ever since I started befriending my coworkers and going out with them (since last year), I have caught at least eight women flirting with me, not counting a few others for whom I had no romantic interest. One of them gave up on me because of my shyness; some of them I hadn't the courage to talk to and the majority of them I only realized were flirting after it was too late. Apparently, I'm incapable of learning through my past mistakes.
There's also the fact that, even when I'm talking to my friends, I'm usually very blunt and I come across as uninterested and slightly arrogant. Even though I've improved a lot since then, there's still much progress for me to do. Right now, the best I can do is stare at women to show interest, which seems to work until they get tired of waiting for me to approach them.