The man has done amazing work and won an Oscar, but that doesn't explain why he's had over 95 on-screen appearances including Bloodrayne, Freddie as F.R.O.7, Photographing Fairies, Thunderbirds and countless other foolish movies.
I don't know how many times I've been watching either an afternoon Sci-Fi Channel original or a late night sleep aid movie and said outloud "no way Ben Kingsley is in this!" but it's always him.
Maybe the explaination is that he's incredibly versatile and has a universal look allowing him to play a wide range of characters... but, I think he just can't turn down a role. EVER!
This might explain some of it...
