South indian movie make their movies faster thn hindi movies those days. All bollywood films hav started to remake south indian movies, and even directors got to work in bollywood.
So if the south indian directors presumly from malayalam and tamil cinema got an opportunity to make films ther, thn obviously south indian actors follow the directors and see wht they can do in their movies.
But, bollywood never attempted to recognize south indian actors in those days so don't assume tht these actors left b.c they did not gt recgonize. Whatever chance they got w.hindi directors, they worked in their films, now if hindi directors always think of rishi kapoor,big b, and other kapoors and khans instead of south indian directors, its only their ignorance tht lead the south indian actors to walk away.
Anyways, see south indian actors tht acted in hindi cinema i.e kamal hassan, rajinikanth,mohanlal in their own films and you'll see tht their films in the south ar much better thn hindi films, and thts why the prefer to work w/talented directors in the south.
Especially kamal hassan and mohanlal. Both of them got national awards for their acting, and their films in malayalam and tamil got the most national awards thn all the kapoors, bachans,kumars, and khans.
Mohanlal in aag ws ram gopal varma's fault, you can't hate mohanlal b.c the public hated ramu for remkaing a classic in the first place. So take your baap and beta philosophy out on ramu's head.
