Grew up reading the comics - Marvel very rarely keeps to their origin stories.
the hulk was hit by radiation from a gamma bomb in the desert. the first movie has him dosed by a lab experiment, the second movie has him do something else too.
Thor - started out as dr don blake? no dr blake in film.
Avengers changed the line up and even kills off long standing characters.
iron man was Tony Starks body guard for years - never even attempted that in the movie.
Fantastic four second film same again. no radiation belt? some dimensional crap.
ONLY Marvel does this... DC sticks religiously to their guns. Batman and Superman solid origins.
Dr Strange - the new one from Marvel, has a female ancient one? so PC.
my peeve is basically the contribution by Stan Lee is thrown out the window. Stan contributed all that schmultz and soap story telling. Character driven story lines. They've stripped away the substance and replaced it with pure spectacle. All that super quick metal shredding that's part of the transformer series.