And yet, that's what you expect the developer to do when they release single-payment software. You expect to pay them $60 once and then release ongoing updates and bug fixes.
Ulysses is a pretty mature app. Give me a break. This isn't Illustrator or Premiere Pro, with constantly-changing use cases. It's a
text app.
When I pay for a piece of "single-payment" software, as you put it, I'm, you know,
buying it. I've been using the current OmniFocus (at $80 for the Mac version + $20 for the iOS version) for a few years now, and it hasn't added any signficant new features in quite some time. And that's fine because it works as is. When they push out some big new update, I'll happily plunk down another $80 if need be, secure in the knowledge that if I choose to, I can make
no further payments if I don't want to.
Same with Screenflow. I've been using that for three major versions now, and paying for each of them. There are basically no changes beyond the occasional bug fix within a major release, and then I get promo pricing for the next one, and I usually bite because there are a few cool new features.
And sure, one expects bug fixes within reason, a few OS compatibility updates -- but if the next MacOS beyond High Sierra broke something fundamental about OmniFocus or opened up a bunch of new features and they had to code a whole new app, again, happy to pay.
This setup is no different. The only change is you now spread the payment out throughout the year. They still provide those bug fixes, small feature additions, and other changes on an ongoing basis.
But it is different. The moment you stop paying, the software stops working because you're renting it. Basically what it is is asking payment in advance, and a blank check to just keep on modifying it regardless of how necessary the revisions even are. Why not just use Kickstarter at that point?