Software rental is a con unless over the course of time the software genuinely gets additions that you want and gets no additions which you did not want. But the software will one day reach the point where it cannot be improved in any meaningful way. At that point, the rental price should be reduced to a lower level to reflect the lower amount of work being put into it, adding the occasional small thing and fixing anything that needs it. But which companies are honest enough to do that!

Windows and especially Office is already at that point. What else can you possibly want it to do? It does to much in my opinion. They could probably strip 75% out of it and no one would notice except for that 1% of users that love to do arts and charts (Powerpoint) and jerk off over Excel spreadsheets with fancy formulas.