FileMaker made my week, albeit in its customarily soft-spoken and modest way.

In a month when I have been using my business accounts database quite heavily – for annual income tax and quarterly VAT (sales tax) deadlines – I am used to facing at least one update to FileMaker Pro. This used to entail a full download of the updated app, but FileMaker has at last switched to incremental updating. This time the download was tiny, which cheered me up as I ground may way into the figures.

Otherwise, what should have been good news, the launch of Setapp, turned into disappointment.

If you want to acquire a new car, there are several different mechanisms for funding it. You can walk in to the dealer with a case full of money (or arrange an electronic transfer) and drive out owning the car completely. You can borrow some or all of the cost, and repay that loan until you own the car. Or you can pay a monthly lease/rental/hire charge to use the vehicle without it ever becoming yours.

Software has always been a bit different, because it is intangible, and in the eyes of the vendor has only ever been ‘licensed’ to users. Whatever the technicalities, in practice this has meant that you purchased a copy of the product, and provided that you kept within the terms of the licence, you could use it for an indefinite period. This is effectively outright purchase.

The problem with outright purchase is how to handle updates and upgrades. I’ll distinguish here between upgrades, which replace your existing product with a major new version with additional features and capabilities, and updates which largely fix bugs and only bring minor improvements. Generally speaking, in the outright purchase model the cost includes updates, but you have to pay again for an upgrade. In most cases, existing users are offered upgrades at a reduced price to encourage their loyalty to the product.

Although Apple’s App Store is a different way to deliver purchased apps, it basically sticks to the outright purchase model. One difference is that there is no obvious provision for discounting the price of upgrades for existing users. Some developers have found a way around that using in-app purchases, but it is rather clumsy, and a kludge rather than a feature.

One of the major innovations with the App Store is the ability to use its apps on multiple Macs, which was always a thorny issue with traditional licensing methods.

Four years ago, Adobe switched to an older model of software acquisition, the pure rental. In the days before desktop computers, most software licensed to larger computers was paid for on an annual lease or rental basis, and that is what Adobe thrust at its users when, in the summer of 2013, it ceased selling its Creative Suite apps under the outright purchase model, and only offered them through Creative Cloud.

One major difference between cars and software, when considering acquisition, is that it is easy to replace a car with a vehicle from a different manufacturer, but switching from one suite of apps to another can be a huge wrench and a big problem. If you are leasing or renting a car and wish to downsize to save money, go without for a while because you’re on a low income, or want to get fit by cycling everywhere, that’s not a problem. With software, it’s usually disastrous.

The reason that software rental cannot let you continue using the last release of the software which you have been using is the hitchhiker problem.

If rented software continued to function when you discontinued paying the rent, there would be nothing to stop you renting for a month, then cancelling the rental, and working on with products that cost hundreds of $/€/£ per year. The next time you wanted them upgraded, you could then rent the new versions for another month, cancel again, and your upgrades would cost of fraction of what they might under outright purchase.

So when you cancel your rental payments to Adobe for its CC suite, the following month all those apps are dead in the water. You cannot use them to access any of your existing files. The one exception to this appears to be Adobe Photoshop Lightroom, which Adobe promises does still work with restricted functions.

My disappointment with Setapp is that it has adopted this same rental model for the bundle of products which it offers, albeit for a much smaller monthly rental than Adobe CC. According to Setapp’s own Q&A, when you cease paying that rental “you won’t be able to open apps from the Setapp folder.”

Such software rental is best for businesses, where it eliminates capital in favour of revenue expenditure, which normally carries tax and cash-flow advantages. It is highly beneficial for the vendor, because it locks users in to continue to pay their monthly rental. If you need to cut your expenditure – maybe you go back to college, or can’t work for a while because of illness or injury, or retire – it can be catastrophic, forcing you to keep paying the rental in order to retain access to your existing documents.

Fortunately, Setapp’s rental system is not the only way to acquire the apps which it offers in its otherwise quite attractive bundle. Most can still be purchased under the long-proven outright purchase model, either on the App Store or direct from the developer. I know which I will continue to use.