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There is a large random
factor in the success of any company.  So the guys you end
up reading about in the papers are the ones who are very
smart, totally dedicated, and win the lottery.
Certainly Bill is smart and dedicated, but Microsoft also
happens to have been the beneficiary of one of the most spectacular
blunders in the history of business: the licensing deal for
DOS.  No doubt Bill did
everything he could to steer IBM into making that blunder,
and he has done an excellent job of exploiting it, but if
there had been one person with a brain on IBM’s side,
Microsoft’s future would have been very different.
Microsoft at that stage had little leverage over IBM.
They were effectively a component supplier.  If IBM had
required an exclusive license, as they should have, Microsoft
would still have signed the deal.  It would still have
meant a lot of money for them,  and IBM
could easily have gotten an operating system elsewhere.