This is not true.
When you pay up front, the developer has an incentive to make the product right the first time; instead of releasing a buggy product because it can always be patched later.
In the pay up front model, if the initial product is crap, then nobody buys the next version. That is the incentive to release a quality program the first time around.
Then the developer has an incentive to make the next version so much better that people who like the first product will buy the new version.
If you pay overtime, the whole game is “how can we make this person love the shit out of this thing for as long as possible.”
No, if you pay over time, the whole game is "how can we keep this sucker on the hook and milk him for monthly payments for bug fixes and things we should have done the first time."
For example, millions of people pay repeatedly for WordPerfect from version to version for decades because it just kept getting better. That's how it was done until very recently, even with operating systems.
When you pay upfront, the dev is not incentivized to try and keep you. So the product gets worse and worse until it dies.
If you pay overtime, the whole game is “how can we make this person love the shit out of this thing for as long as possible.”