Because he has no superhero's yet he has some of the worst villains successfully overcome and gone through so much! The Batman family, his movies and his whole entity is amazing ;)
The entire grim, twisted mood of the whole franchise. Allot of the comics/shows/movies are realistic (since most of the characters do not have super powers) and deal with difficult themes like tough decisions, death, and mental illness.
Also, heroes is only as good as the threats they face, and Batman has the best rogues gallery of any comic book hero.
Because he isn't like the other hero's he doesn't have powers for one so he makes all his weapons and gadgets and stuff so it just makes his that much cooler and the way he takes down villan after villain is amazing because half the time he is using brute strength as his only weapon.
