That's basically a subscription model, no? Say USD80/12mo makes ~USD6.99/mo. I'm still not sure how I feel about renting software. Even though I feel that's where our industry is heading with the app stores and their restrictive pricing model.
With what the grandparent proposed you wouldn’t have to upgrade, you could just continue using the old version.
Seems to be popular with making developer tools for some reason. MonoTouch, RubyMotion and Apportable all use it, for example.
I watch the phpstorm/pycharm EAP's like a hawk as they are constantly adding stuff that will make me hand over money :).
Sketch 2 can't open Sketch 3 files.
Somehow you're forced to update if you intent to keep using Sketch.
As you mention, some users don't like the "service" model, so you could present options along these lines (scale values to fit your product):
$120/yr ($10/mo) as a service, or... $150 to buy now with free minor upgrades and $100 (or scale to be fair for the magnitude of the upgrade) prorated major upgrades.
So I can choose to pay more up front and maybe save a little bit of money in the long run if I choose to keep upgrading, but definitely have access to the software I bought and am familiar with even if I decide I don't use it enough to keep upgrading.
From there of of four things is likely to happen:
1) They decide they don't like it and end their subscription quickly. Since it was cheap, they don't feel cheated and are less likely to smear your brand.
2) They like it and are lazy/preoccupied/like-the-convenience, so they keep the subscription.
3) They like it enough they decide to buy a license so they can save some money long term with upgrades and have more freedom with how they use it.
4) They're not sure if they'll use it enough to justify a continued subscription. If they need it enough, they buy a license without planning to upgrade as a compromise. Maybe they'll decide to upgrade later. If they're not sure, they drop the subscription and maybe buy a month at a time when they need it in the future (you can encourage more frequent users not to do this by offering a 20-25% discount to prepay a year for the service).
Monolithic desktop software like this would pull in more users and revenue with flexible rent/buy options.
I'm also more confident that you're motivated to keep pushing out big meaningful upgrades if you have users that you actually actively have to convince to buy them over what they already have.
Not really. A subscription model means the software stops working when you stop paying. @entrode's pro-rating idea is just more granular about how much of a rebate you get off the next version.
Maybe they do that because it would be impossible to enforce anything else (paying one month gets you the full source code), but it's still great that the license allows it.