Filmmaking is nothing if not a stressful business - even the smallest, most modest movie is a result of dozens or even hundreds of people combining their skills to deliver a releasable end product.
The expensive, time-poor nature of filmmaking means that tensions frequently run high on movie sets, yet once the shoot has started, it's extremely rare for directors to take their ball and go home.
For one, a director's exit typically signals a major breakdown in communication at some point, or that they've lost any and all confidence they had in the film going in.
While most filmmakers would likely soldier on with a bad shoot and simply chalk it up to a poor experience in retrospect, these directors all ended up quitting movies in the midst of production, while precious filming still needing to be completed.
The reasons are myriad: perhaps the director had major disagreements with a producer, clashed with their leading man, or simply had a personal situation they had to attend to.
But in each case these filmmakers did the rarest thing of exiting their movie right in the middle of shooting...
10. David O. Russell - Accidental Love
David O. Russell's follow-up to I Heart Huckabees was originally supposed to be Nailed, a political comedy co-starring Jessica Biel and Jake Gyllenhaal.
Though the film began shooting 2008, it was reportedly shut down 14 times during principal photography due to nonpayment of cast and crew, prompting Biel and Gyllenhaal to stage a walkout.
The film sat in production limbo until 2010 amid various financial woes, at which point Russell was summoned to complete reshoots for the film.
But Russell refused to return to shoot new material, claiming that original financier David Bergstein sabotaged the production for his own gain, while also objecting to Bergstein asking other producers to take 50% pay cuts.
As such Russell quit the film and the reshoots were eventually conducted without him. Due to Biel and co-star Tracy Morgan's contractual requirements, however, they were forced to take part in the reshoots unlike Gyllenhaal.
Nailed was eventually renamed to the more mainstream-friendly title of Accidental Love and released in 2015, where it unsurprisingly received predominantly negative reviews.