(edit: I don't know if this is actually true of Final Cut Pro's model)
If you only need Final Cut Pro for a 2-month project, it's amazing because you'll save so much money.
And any time you need it again, you just resubscribe. You're never losing access permanently, it's just $5 away.
The point is that the flexibility and ongoing updates are a more beneficial tradeoff.
A lot of people (like myself) simply don't care about owning equity in software, so we have eternal access. It's just a tool, and it loses value over time without updates anyways.
Why? It will continue to do exactly the same thing. If that thing had no value to you why are you getting it?
Edit:
> Because the world moves forward. Something that might have worked well 5 years ago but has had no updates or improvements to keep up with competition is ultimately not as useful as it once was.
Not everything is a javascript library though.
The parent poster you're replying to wrote "loses value" not "no value".
As an example, I have the last version of Adobe Creative Suite CS6 ($2599) that had a permanent license with CDs instead of subscription download but that came out in 2012. Over the last 11 years, that old software has continually lost value.
The old version cannot easily be installed on newer macOS versions after Catalina. I can't freeze my os version at Catalina to satisfy Adobe CS6 because other tools like the latest Xcode and Logic Pro forces you to upgrade to newer macOS versions. I can't freeze Xcode at an old version because Apple's App Store rejects apps built by old versions of Xcode. And then you have the lack of desirable new features. E.g. the old Premiere Pro in CS6 can't open newer ProRes HDR HLG files.
The rest of the world around a particular software changes which then affects its value.
So "owning the software forever" doesn't necessarily translate into continually using it forever in a practical way.
The way we use a platform over time changes, as does options in the market and the way a business treats that platform. If we can export and keep our IP that was developed through the platform, it's not a bad thing to have the option to cut and run without having sunk purchase costs.
It also provides a signal for the business's product team to use with finance to argue for how to continue updating the product. Ongoing engagement metrics and new conversions are continually reviewed. How those change with the release of, or marketing of, different features directly drives the development of the platform—it should in the best case see a more useful product in our hands over time.