The current generation of operating systems is much more powerful than
they were in the days of DOS. We demand more from them now than ever
before, and they've had to keep up with all of our needs and wants. As
you know, an OS isn't just another standard piece of software. Instead,
an operating system has to manage a complex set of system-level
processes all at one time, and it's quite literally responsible for
running the show. Therefore, it's easy to see why these systems take so
long to develop and successfully release.