Frank Robinson cards seem to get the shaft...

[Exhibitman]

One of my all time favorite players but I think he was unfortunate to have played in an era where he was not even among the three best starting outfielders: I'd take Mantle, Mays and Aaron over him (and perhaps even Clemente). He was perhaps the fourth or fifth best--and he is priced accordingly. Kinda the Ken Norton of his era (stuck behind Ali, Frazier and Foreman).

I do think personality has a role too. Mays was probably better than Mantle--except for a few peak seasons--but is priced lower than Mantle IMO in part because he is a real turd in a punchbowl at shows, while Mantle for the most part was cordial or even friendly at times. I know that he had that effect on my collecting. Mays was my favorite as a little kid but when I met him (or rather had him not even say hello in reply to my greeting as he was signing my baseball at a show) I sold off my collection of his cards. Sometimes meeting your idols is a bad thing...