Fist time I saw it, I had a flashback to the times when I worked for HP, and they were making some huge SAP knock-off, and that system was so labor-intensive to deploy that their QA process involved actual patches. As in pre-release QA cycle involved installing the system, validating it (which could take a few weeks) and if it's not considered DoD, then the developers are given the final list of things they need to fix and those fixes would have to be submitted as patches (sometimes, literal diffs that need to be applied to the deployed system with the patch tool).

This is, I guess, how the "patch version component" came to be in SemVer spec. It's kind of funny how lots of tools are using this component today for completely unrelated purposes... but yeah, LSF feels like the time is ticking there at a different pace :)