I think fear of approaching is essentially a simultaneous flooding of a plethora of insecurities, of the realization that disparity exists between true perceived identity and a desired ideal.

I agree that either thinking too much or having too many insecurities are detrimental to approaching women.

I also think that “hi” works much better if the woman has already pre-selected the man, as shown by body language cues. If she hasn’t, it might instill psychological reflexes, her defenses quickly raised (which can be diffused by directly stating intentions).