That's the type of applications I build. Essentially decision making tools.
Users from clearly legitimate businesses sometimes sign up, start the billing and then just disappear. No response to emails, support tickets etc. I'm often tracking down billing teams 18 months later trying to convince them they really do use our API, and that if I can't get them to renew their billing details I'll have to eventually disable their access due to non-payment and then their infrastructure will no longer have up-to-date exchange rates! In these situations I sometimes disable access for 24 hours and then re-enable it to see if this drums up a dev I can speak to. It's quite a process but I've won some "customers for life" by saving them from downtime they would have had if I just cut them off.
I can see why they did this since there were only a few TLD's back then compared to now and thus owning the .com for a specific keyword was a legitimate signal. I can't remember exactly when this got deprecated as a ranking factor but it was very useful for the first few years!
Over the years I've accumulated the domains of failed competitors that had more punchy names and toyed with the idea of rebranding but don't think it's worth it. The SEO risk of a rebrand is substantial concern.
However, that said, I think in the majority of the actual cases I'm describing above the cause is more a combination of 1.) the surprising percentage of tech companies that appear to be in a state of continual organizational dysfunction and 2.) how API's are inherently a background type of thing like lloydatkinson wrote!
In about 1 in 10 cases I'd also say the cause is actually because of merger/acquisition - which is just always a complex and organizationally challenging process.