Look at Novel, it worked so well it went bankrupt. There was no need to buy the next version.
Look, every working version of windows was followed by a lousy version.
I remember Novell well...it was king back in the days of DOS. And I remember "the other" network system very well back then, Artisoft LANtastic....worked with that A LOT.
But I'll have to disagree about "every working version of Windows was followed by a lousy version.
DOS and Win3x...incremental improvements. Yeah, DOS doesn't literally get covered by your statement, but Windows 3...does. It...slowly got better.
Windows 95..original, was called Windows 95a. Quite buggy.
Windows 95b was better..by quite a bit.
Windows 95c was rare
Windows 95d...better yet.
Windows 98 original version...meh.
Windows 98SE...pretty darned good
Windows ME was horrible, outsourced at the last minute because a consumer version of Windows 2000 didn't come to market on time (all the multi media stuff needed for a consumer version).
Windows 2000 was...GREAT, for business networks, and IT people. They loved it.
Windows XP...fanstastic.
Esp after SP2...very solid...and long lived.
Windows Vista..yeah, sorta sucked.
Windows 7...danged good.
Windows 8...yeah, meh.
Windows 10...I've been with computer since Fortan and BASIC...and in great depth since DOS/Win3x...and W10 is my fave by 88 thousand miles. IMO, Microsoft did good with W10. You can go months and months without rebooting, and laptops...you can open and shut the lid and just "sleep it" for months and months on end. It never complains. yeah, better to reboot it once in a while to get updates in, but...the OS doesn't act cranky from lack of reboots like earlier OS's did.