My monster theory:
1. A monster must be scary and/or abnormal looking.
My theory of the Top Ten monster list from this thread:
1. Its unlikely that they surveyed a large amount of various people of different ages and backgrounds. It also unlikely that they surveyed the majority of the public; for if they did they would have a completely different list that wouldnt consist of The Skinned Werewolf, Shelob, The Troll, T-Rex, The Thing, and Tetsuo. The only people that would give those kind of answers are idiots. If this list was an official and honest one it would look something like this 1. King Kong, 2. Godzilla, 3. Frankenstein, 4. Count Dracula, 5. The Wolfman, 6. The Creature from the Black Lagoon, 7. The Blob, 8. The Alien, 9. Zombies from Night Of the Living Dead, and 10. The Mummy (no, not the remake).
That's a more accurate list my friends. If the magazine would've bothered to consider movie monsters from all years and not just the ones from recent movies, then they would've came up with a similar list.
(And the only reason why King Kong made the list is because Peter Jackson is directing the remake, so naturally, all the fanboys had to rush to his side)