I’ve always been drawn to tortured souls like Edgar Allan Poe, Virginia Woolf, and Sylvia Plath. Learning about their (depressing) lives and heartaches–and in the case of the two latter, suicides–has prompted me to read their poetry and novels. I think it’s especially insightful, knowing the backstories and in many ways, autobiographical elements in their work. For me, that knowledge makes their work more meaningful.
(Disclaimer: hope the above makes some kind of sense. Am highly medicated on Sudafed + Benadryl. Apologies if my rambles don’t read well at the moment.) 
I don’t know if a biography has made me not want to read an author, but their big mouth certainly can turn me off.