Something I never understood: how can movie and music quality be measured by counting one-off paying audiences (cinema goers, pre-streaming album buyers)? Peopl

Something I never understood: how can movie and music quality be measured by counting one-off paying audiences (cinema goers, pre-streaming album buyers)? People will only know how good it is once they watched it and therefore already paid. There is no money back if you don't like it. Hype / marketing and timing must be a huge part of what makes box office numbers.