I stand by my statements, but will throw in IBM also as motivators for the PC market(Apples biggest mistake was to not allow cloning).
Actually, no. Bill Gates, having no OS and only a tiny piece of the compiler market, had his mommy get him the gig with IBM.
When IBM came to Gates, Gates said, "Sure, I've got an OS for you. Come back in three months," and IBM left happy.
Gates then went to go see Tim Patterson at Seattle Computing who actually did have an OS called Quick-and-Dirty OS or QDOS. Gates bought QDOS for $75,000 and after renaming it MSDOS, he delivered it to IBM.
It was widely known that QDOS was pretty much ripped off from CP/M, written by Gary Kildall.
Wary of being sued by Kildall, IBM offered to license CP/M from Kildall and make it available for the IBM PC too. When Kildall's wife threw some IBM suits out of their house because they wanted her to sign an NDA, IBM fixed Kildall. They priced CP/M at $240 and MSDOS at $50, thus ensuring that DOS would win out.
So, no, Gates did very little except commit fraud by selling something he didn't have.