Comment by chii
> stops being maintained and the lack of updates makes it fatally insecure or something
which doesn't happen instantly. For example, the end of life of the old java versions (1.5, 7 and 8 etc) - plenty of companies simply just paid a support fee and get support, while others paid to upgrade (or even change stack).
Most open source software, even with lack of updates, does not immediately start failing. The huge amount of time and leeway, even with security issues, is what prevents it from being critical, and prevents OSS from causing a bankruptcy.
> what prevents it from being critical
Well, there's plenty of mission-critical FOSS used by plenty of companies. But you are right in that it doesn't just fail one day, and companies have plenty of time and options for dealing with abandoned FOSS.
(Which is one of the major benefits of FOSS. It's more likely with proprietary software that it can just disappear one day, with little recourse for users.)