Most Helpful Guy
As a former shy guy, I would say that approaching girls that they are really crushing on seems like a puzzle that they only have one shot for. They feel like there is a specific conversational formula that they must abide by or else they would scare the girl off and never see her again. Like they have to do this when the girl is playing hard to get, we have to do that when there is an awkward silence and so on. It feels as formal as a job interview when we approach girls we like. It took time for me to realize that I was making it harder than it needs to be when I am with a friend of mine who has many female friends. Basically, they are human and there is no real need to be that formal.
We also feel that sometimes we need to have some previous association with each other otherwise, you immediately fail because she does not know who you are and therefore does not want anything to do with you. We feel like we need to have a lot more experience with her than we feel like we currently have. Again, this falls under the human thing. It seems silly I know but the shy guys (at least I was) are really that certain that they would fail and are really hesitant to try to ask girls out. If a girl approached him I think it would immediately erase the doubt. Ask for the number because that is usually how they get used to talking to you.