> If you sell a one time license to somebody there is no incentive for the seller to keep making the product better, to care keep caring for you.

I strongly disagree on this one. If they want to sell you version 2.0 (upgrade), they better make sure those new features are worth their money.

With a subscription model, you either keep paying them or you lose it all. Why would they improve their product when you're already paying them x/month?