Seems to me that you get paid either way. It's the client that loses if they don't provide the content they promised.
I think at some level people either decide that they don’t care about their work or they care enough that bad work is painful. It’s not for me to tell you or anybody else which way to go with this, but for me, bad work is painful and it’s up to me to work things out with clients such that I do good work and they are happy with the results.
My main client is the one I'm obsessively steering toward great software.