Apple's Busy End of Year
Ironically, when Microsoft produced their handheld operating system -- Win CE -- the desktop mindset caused them to fail against Palm, a company with a handheld mindset.
The lessons are obvious. Don't cram a mainframe into a desktop. Don't cram a desktop into a handheld. Prowess in one domain can be baggage in another.
For a deep retrospective on the failure of OS/2, see Ars Technica: Half an operating system: The triumph and tragedy of OS/2. For a shorter take, click on the "We asked for it" image to read my essay which appeared in Computer Language November 1990. And for a riveting read on Palm's battle with Microsoft and the struggle to IPO, visit the Internet Archive for Piloting Palm, by David Pogue and Andrea Butter.
This year end, we saw Apple with an uncharacteristic flurry of releases. In part, that's because when Apple produced the iWatch, the company did not cram an iPhone into it. Instead, Apple wisely tuned iOS to match their devices -- desktop / laptop, iPhone, iPad, TV, watch -- with macOS, iOS, iPadOS, tvOS, and watchOS. This has meant considerable release coordination to make sure they all function well together, and while it's a lot of work and angst, history shows this is the right move.