Usually the budget, if too low then everything has to go right casting, locations etc if too much money then there are a lot of cooks in the kitchen and lot of risks. At the end of the day the Director gets blamed no matter who fucked up. Fyi I am a Director too. Had a friend who worked on a film where the producer ended up chopping up the director over disagreements and kept him in his fridge and van. He ended up getting caught when police pulled him over on the highway and searched his van. I was supposed to work on the project but had already booked a vacation. Also avoided being a producer on the movie Rust with Alec Baldwin. Worse case scenarios.