I think there is more to it than just looks, although, I have yet to put my finger on it.
My late sister was pleasant looking but nothing special, but she had a certain charm that meant people fell over themselves to help her. In the days before suitcases with wheels, there was always someone around prepared to help her with her suitcase, while I stood by her carrying my own suitcase without any offers of help at all.
She had the kind of job, where a death in service meant a public memorial service in a City church organised by her employer, and so many people told me how surprised they were by how devastated they had been by her death - but there was just a certain something about her.
I have met other people with this same indescribable uality.
Yes, prettiness does get an instant response. A bit like seeing a lovely dress in a shop window, seen, admired and walk on and forgotten. Others have that charm that lingers and stays with one.