Giving a woman your number is just like junk mail and ends up in the same place. To be able to close a "sale" like that you need the personal interaction, a good reason and some action (an arranged meeting to go to later for an agreed purpose). Otherwise it is not impossible that the woman will call you but the odds are not favorable and you are wasting your time. There are however exceptions to this rule.
For example if you are in a night club and the woman you fancy is looking at you protected from a bunch of male friends. Then if you walk to her and give her the number she will think you have balls and it is all a bit illicit (make sure you do it when nobody else is watching).
You're a big playboy, Lobo. :)
Well, I suppose I slowly got better with age, it is the mileage I guess. I am quite particular with the girls I go for and thus have to increase my hit rate otherwise I would still be a virgin…
Also I like to observe how things work, girls being just a more complex "machine".