Depends on the ending itself, though I feel like there's a lack of bad i.e. tragic endings in the industry as they usually leave to an abrupt end. Whereas happy endings allow you to continue with the route
I'd say the writing and MC, primarily. I've dropped a lot of games due to poor writing, broken translation, lack of dialog complexity, etc. But also if the MC sucks imo, I would often drop the game because forcing it just doesn't work.
I did my best but was unable to find any, such a bummer. Your statement about real life girls makes me think of a live action visual novel that was perhaps never released
if you think of any other clue, let me know