I think DTB makes good points.
Face it, the devs are very much in the position of the officers of public companies. Such officers feel their primary role is to increase GROWTH of the company, or more specifically the stock. At a certain point you hit a wall—how can a coffee shop sell more than X cups per capita, per day, lol? Add food! Then when everyone is eating and drinking, then how do they grow? Sell toilet access?
The devs are in a similar position with new releases in the same "family."
The execs want to see something NEW. Old bugs? Who cares, didn't stop sales before, and they can have someone in the team dribble out a patch or two while they work on the next, unfinished game with NEW stuff that is obvious.
OSes have the same thing. A new Windows has to LOOK DIFFERENT. Never mind that they don't fix old bugs that are deep under the hood—in order to score a sale it has to add NEW FEATURES, even as they add new bugs.
A couple years ago I was doing some remodeling downstairs. At the same time, I needed to do the roof. Turned out that the roof needed a total replacement—along with my HVAC which is up there. I ended up spending more on the roof than my downstairs Library-media room/guest bedroom/bathroom (total maybe 800 ft^2). More on the roof, and guess what, it's 100% invisible. HVAC works as before, roof works properly, but no one but me (and now you all
) will ever know. HAD to be done, but if I was a software company, I'd just have done the pretty downstairs remodel and left the roof for the next guy.
A SH4 example. The paid add-on. It added u-boats instead of useful PTO content, and into the bargain it didn't fix any bugs to speak of, or primary errors in the initial game.