They lost their most skilled staff from the 1990s era due to early retirement. They fired all QA staff. Nowadays they have a big piles of legacy codebases. They outsourced or better say moved development of many products to India. Nowadays you really feel the lower skilled work force (compared to 1990s staff) and no QA to speak of everywhere in there products. Their product feel like designed by people who have little engineering knowledge, a far cry from 1990s software UI. Well it already started with WinXP that contained already HTML based UI parts like "software" control panel, and many more parts - an undocumented new UI API where the EU fined them. Plus the 1984 style spyware features their Nadella CEO introduced and forces upon end consumers like there is no tomorrow.