"According to several people familiar with the new process who asked not to be named, the new workflow caused issues for developers as they were not quite sure how to balance time devoted to testing versus building. Further, having spent years coding and not performing detailed and prolonged testing, their methods for quality control were not to the same standards as those who were dedicated to the task. Under the new process, the time allotted to building out new features includes testing the code as well, which it previously did not, which means that those engineers who are accustomed to the old style, now find themselves under more pressure to turn out quality code in a shorter period since they have to do the detailed testing. The end result, as we have seen with Windows 10, is a product with more bugs and it's starting to show the weakness of the new process flow."
Apropos of nothing, ZDNet reports that the latest Windows Phone 10 release has been pulled because of bugs in the installation process and also reports on Microsoft's official apology for the numerous issues that have plagued it's recent Surface Pro 4 and Surface Book devices.
"There are some good people in it, but the orchestra as a whole is equivalent to a gang bent on destruction." -- John Cage, composer