It is kinda partially sales, that goes into it. They select a certain number of "big names" every time, ignoring actual influence on the world of rock, because they need to sell tickets to the charity dinner and nobody will come if it's a load of random people they've never heard of. The Rock and Roll hall of fame is a joke, I am honestly surprised anyone continues to give a crap about it. Remember the "voting criteria", as it was put in this thread, is not laid out anywhere, it's up to the vote of a VERY small group of people, it's all about their own personal taste and who they think will draw people.
Considering Laura Nyro is in the hall of fame, record sales and popularity do have absolutely nothing to do with the nomination process. It's all down to whoever the small committee likes enough to nominate.
Any way, instead of giving a snappy answer about the HoF being a joke, here's a few bands who deserve to be in the hall, unquestioningly:
Kraftwerk
Bauhaus
Joy Division
Depeche Mode
T. Rex
The Cure
Ministry
Throbbing Gristle
Nick Drake
Misfits
Venom
Duran Duran
Stopping before I get all wistful and depressed about some of my favorites getting snubbed year after year.
Afraid nobody 'round here
understands my potato
They think I'm only a spud boy
looking for a real tomato
Devo - "Smart Patrol/Mr. DNA"
It's really the "Jann Werener's favorite band's" Hall of Fame (VH1 should take it over as they do much better than Rolling Stone) to the point where he lowered the entry age to 20 just so Nirvana could get in sooner. Rush is proabably the most infamous band denied entry, but here's a list from me, apologies if they are already in, and I am aware some of these bands are too young:
RHCP
Deep Purple
Alice Cooper
Megadeth
Anthrax
Slayer
Iron Maiden
Judas Priest
Radiohead
Rush
Yes
Genesis
Alice In Chains
Pearl Jam
Soundgarden
Nirvana
Television
Guns N Roses
KISS
Beck (just for you A_C)
The Smiths
The Cure
New York Dolls
The Pixies
The Replacements
Stevie Ray Vaughn
T. Rex
Weezer
Stone Temple Pilots
Beastie Boys
Motley Crue
Weird Al
Remember zeppelin1969!