Both WordPerfect and Lotus 1-2-3 faced some of the same sorts of issues in the early 80's, and both product teams made choices that left them unable to respond effectively to Windows.

To set the context, rewind the clock back to 1987. (Bear with me here.)

In 1987, the IBM PC (running DOS) is well established as the dominant business personal computer. However, thanks to the easy availability of Microsoft's DOS, and the almost completely open hardware design, a huge array of PC clone vendors has effectively taken over the market. In 1987, the clone vendors own the low end on price and own the high end on performance. (Compaq beat IBM to shipping an 80386 based machine by a year or so, and the Deskpro 386 was three times faster than IBM's best PC AT). IBM has effectively completely lost control of the market they started.

To respond, IBM develops a completely new line of PC's, the PS/2, and works with Microsoft to build the next generation OS: OS/2. OS/2 is intended to be the first mainstream multitasking, protected memory OS for personal computers. The combination of the two is supposed to advance the state of the art so far, that (in combination with IBM's proprietary bus license) the clone vendors will be completely shut down and unable to compete. Both IBM and Microsoft convince the ISV's that OS/2 is the wave of the future and where new platform investments should be made, instead of Windows. Both Lotus and WordPerfect release all sorts of cross platform versions of their flagship products (VMS, SCO Unix, NeXT, etc.... everything but Windows, because it's obsolete.)

By the time 1989-90 rolls around, it's pretty clear that IBM's strategy has fallen apart. The machines are too expensive, not compatible enough, and the features that customers actually care about (VGA, etc.) are all available on cheaper/faster clone machines. OS/2 has also fallen short because it's expensive and requires special software to work as it should. (For existing DOS software, old OS/2 was a major step backwards).

Into this chaos, David Weise and Murray Sargent, both of the Microsoft Windows team come up with a way to run existing Windows applications in protected mode. (This is a non-management supported skunkworks project... MS management was still behind OS/2 at the time.)

http://blogs.msdn.com/b/larryosterman/archive/2005/02/02/365...

What winds up happening is IBM and Microsoft split up their partnership, and Microsoft charges forward with protected mode Windows, in the form of Windows 3.0. Windows, always cheaper than OS/2, now contains all of the important OS/2 features and works better than OS/2 for your existing DOS programs. Basically in an instant, the entire momentum of the industry went from trying to figure out how to make OS/2 work to a wholesale adoption of Windows. The ISV's had to respond in turn.

For Microsoft, this was easy... they'd always been on Windows, mainly because they had to. For everybody else who'd been driving to OS/2, it was a major change in priorities. API's were different, the graphics model was different, in some cases, companies had to switch to GUI's from CLI's... I don't think it was premeditated, but the change in platforms ave Microsoft a huge advantage that they absolutely jumped on.