When I wasn't sure I wanted to continue, the hiring manager called me for 45 minutes to discuss why, and convinced me that I should continue without making any promises and without lying about the fact that my concerns were real and that it wasn't garaunteed that my concerns would be fixed, but I felt better because he told me about how they're trying to fix them. Contrast that with my last company which blew smoke up my ass for the whole interview process and later I found it was a very badly run company on top of badly designed tech and bad financial modeling and that anything to fix it was impossible because of the politics.
Further, I've been talking to the interviewers like they're real people rather than some god sent down to flummox me with dumb programming exercises and show off how cool they are.
I'll never do another interview the "old way" again, I like being treated as a human in a two way process rather than a one way information extraction exercise.