I believe Adobe has guaranteed its profitability by forcing the subscription model on its customers. A decade ago I bought Adobe CS in multiple discs. While the company regularly asked me to upgrade, I didn't have to so long as what I had could do what I needed it to do. So that was a one time purchase. But with the subscription model, you never own the software and will have to pay for as long as you use it, even if rates go up. Over time, the customer will shell out a lot more that way than if s/he had bought the software only once.