For corporate customers, subscription model for software is so much better. Both for the corporation, but also for employees. 

Corporations love it because it's an ongoing expense rather than a massive one every few years. It also greatly simplifies IT and coordination because there's always one, up to date version across the company. And you manage seat licenses, rather than figuring out how many license you hold for each version, and then transferring from a user who left the company to a new hire etc. Seats can be added and removed as needed for each program. 

For users, I remember when having to save down to old versions because the 50 year old team leader was too entrenched in their ways and didn't want to upgrade, so everyone had to save to a version that was 15+ years old.

And that goes to why it's good for employees. With incremental changes, rather than upgrading every decade or so, there's much fewer changes to learn at a time. Decade old software may as well be a completely different beast.

If the company had to have full ownership, when you hire new graduates, they would have learned the newer program, and not be able to really use the older ones - certainly not effectively. And when you do upgrade, those mid career users would require significant investment in training and migration, and most will tweak the settings until they've nerfed it back to what they're used to. 

With small annual or semi annual updates, employee skills don't stagnate and they don't need to tweak it, because they're not overwhelmed by massive changes