5. Voting: Voting shall be based upon the player's record, playing ability, integrity, sportsmanship, character, and contributions to the team(s) on which the player played.The Pro Football HOF bases enshrinement on only one factor: on-field achievements and contributions to the game.
6. Automatic Elections: No automatic elections based on performances such as a batting average of .400 or more for one (1) year, pitching a perfect game or similar outstanding achievement shall be permitted.
The Rock and Roll HOF criteria are likewise pretty open-ended: voters consider innovation and influence.
It should be noted that the Baseball HOF rules have evolved over a number of years-- it is the oldest institution of its kind. It also bears mentioning that only baseball includes criteria like " integrity, sportsmanship, [and] character". It is also worth mentioning that the Baseball HOF includes, inter alia, Ty Cobb, and Walter O'Malley. (Football has O.J.. Nobody's perfect.)
I'd say that the quality we are looking for is influence, and I think that's been pretty clear up to this point, but I wanted to put it out there.