If you are looking to date women under 30 years of age, I would say you can easily get rejected 19 out 20 times.
Women in their early twenties have such a wide selection, they even reject guys they like. Women at this age are confused. They don't know what they want. They don't understand why they have so many men approaching them and they don't want to get tricked. Women at this age have so many men after them, they are more focussed on how to reject properly without angering the men.
An attractive female in her early twenties will often fall in the category of fear or confidence. When she sees many men staring at her, she might be fearful they will violent. On the hand, other females enjoy the attention.
If you ever go to a night club and there are too many men, you will notice females start to leave. Why? Because more men means more danger in a club. Females only feel safe when there are enough females are around.
Women during this naive age also have unrealistic expectations of men. Because there are so many men hitting on them, they think men are meant to do everything for them. Men need to be attractive, powerful, maybe rebellious and pay for everything and be kind and loyal all at the same time. However, once when reality kicks in usually in their late twenties, they realize their expectations of men will cause them to be manipulated or possibly worse.
However, as females age closer to 30 and older, they get worried that they won't find a mate. Females get older and uglier and males start to die. They're selection becomes less, men become less aggressive as their sexual hormones die. Women, on the hand, their sexual hormones rise and peak at 40. So if you are a male over 30, you will actually find it easier to pick up. Women find men over 30 more mature and stable. Still though, it is still the man's job to approach. So you still need to learn the skills and you will still get rejected, perhaps nine out ten times instead of 19 out 20 times.