XaaS
Microsoft generally insists that users get more value from SaaS because it can be updated more frequently, doesn't need on-prem maintenance or hands-on admin, and … and well … cloud is just really good, okay?
This is like the argument that if you spend a lot more on things that you don't need or want but are marked down from their original overpriced amounts you are in some way saving money. In this particular case, it's also about the difference between purchasing something and renting it and it's pretty clear who comes out ahead in that scenario.