That was the slogan of OS/2 2.0. But by then where Windows 3.x was already out and in 386 Enhanced Mode, more than good enough. It also had the extra "escape hatch" of being able to quit to real DOS if a DOS box didn't work.

OS/2 1.x's DOS box was bad, with lots of limitations, which isn't good when most existing PC apps are DOS apps. As for GUI, well, lets call the Presentation Manager 1.x v Windows 2.x a no-score draw.

Well, technically Windows 2.1 (released May 1988) came before OS/2 1.1 (released October 1988). OS/2 1.0 was text-only. So at least for 5 months in 1998, Windows technically beat OS/2.

And OS/2 1.1 was very similar to Windows 2.1, so it's arguable if it was actually much better.

OS/2 1.2 was a massive leap though, not only beating Microsoft GUI wise by a whole year, they even implemented tons of advanced features that we didn't see until Windows 95.

If only every program worked out of the box... :')

And yet it failed in the common user's perspective but I've seen many ATMs run it and those were usually the working ones without BSODs on them.