Just in case any actor got the wrong idea that they werent entirely expendable in the eyes of Hollywoods money men, theyre replaced with surprising frequency in movie franchises.
Sometimes it happens because the original guy was too expensive (and not good enough), as per Terrence Howard in Iron Man, sometimes people just get sick of the role, and other times life (or death) gets in the way. Its usually horrible for continuity, but luckily everyone knows that film audiences are dribbling morons who notice nothing about their favourite films.
Just kidding, youre all special little snowflakes and of course you noticed. Like when Harry Potter films replaced TWELVE of their actors for various reasons. Some were forgivable, but some just seem oddly unnecessary
12. Verne Troyer - Griphook
The Replacement: Warwick Davis
The diminutive actor turned up in The Philosophers Stone playing Griphook, a noticeably smaller goblin who guides Harry and Hagrid down to Harrys vault in Gringotts.
But by the time the character reappeared for a more expanded role in The Deathly Hallows, he had been replaced by Warwick Davis, who actually lent his voice to the goblin in The Philosophers Stone.
Interestingly, Davis is the only Harry Potter actor to have played two versions of the same character, since Professor Flitwick was oddly reinvented between the first and third movies.