It working when you use it and making sure everything is working for everyone are 2 separate things in programming. I'm not very experienced, but have some done some coding and sometimes things will work perfectly in your tests, but then freak out when 1 change is made or it's run on a different system. Bug fixing is time intensive and often thankless, since people complain if things aren't released fast enough but also complain when there's bugs that aren't fixed because the update was rushed.
Obviously, they've said that they were working on it as art was done, but to me it reads like they're doing more bug testing before release. So in theory, there might be fewer reports of "ZOMG THERE'S A BUG" when it does get released, and a corresponding fewer minor bugfix updates.
Though it could be that they were lazy and got less done as the art updates were done, we're on the outside and can only really guess.