The screwed up so bad on win 7 and 8 that they designed a brand new operating system and those who know say it's gonna be their best.
Windows 8.X I'll agree, but Windows 7 has been a solid operating system and currently holds a nearly 60% market share. OS X 10 has been fairly stagnant at just under 3%, and nix combined only holds around 1.5%.
A "bad" OS doesn't get the lion's share of the market, especially in the corporate environment. Most corporate licensees have migrated to Windows 7 (although there is still a small XP market), but many corporate licensees have refused to update to 8.X, mainly because of the metro interface. Windows 10 is most certainly not a "brand new operating system", it's built on the same kernel version that started with Windows Vista (6.0).
Microsoft has a habit of making every other OS release successful. Windows Millennium was a flop, Windows XP was a benchmark, Windows Vista was a flop, Windows 7 is solid, Windows 8 was mediocre, so if history repeats Windows 10 should be a good OS.
There is an issue with a lot of legacy code that uses something like the following:
if(version.StartsWith("Windows 9"))
This denotes Windows 95 and 98 and it was used to determine the version in order to run the legacy code when XP came out. Skipping Windows 9 and going to Windows 10 solved the issue. I can't begin to estimate the number of times I typed that line, in a dozen or so programming languages.
Keep in mind that there is also some internal code that refers to the actual kernel version number. Windows 2000 was actually 5.0, and XP was 5.1. Vista was a totally rewritten kernel and the first kernel not to overlay an MS DOS subsystem, and was designated as 6.0, Windows 7 is 6.1, 8 is 6.2 and 8.1 is 6.3. Windows 10 is 6.4, which designates it as being based on the 6.X code. A "brand new" operating system would not have a 6.X internal version code.