If you're a large commercial software house, with $$$$$ of revenue riding on things working/being able to develop features quickly the usual "contact support, t

If you're a large commercial software house, with $$$$$ of revenue riding on things working/being able to develop features quickly the usual "contact support, tell them about issue, wait for fix" flow can cost you a lot of time and money. Even large businesses that don't produce software as a product often have internal dev teams that customize third party software to their needs (at least in the particular vertical that I'm involved in). It's immaterial in these cases whether the code is properly open source or not, but being able to go in yourself and fix minor bugs that are blocking you in hours/days rather than the weeks/months it might take the vendor to get back with a fix is practically a hard requirement for any dependencies that are core to your business.