It is very simple to say that Ballmer came up short. What's more, as it were, he did fall flat. In September 2000, nine months after Bill Gates named Ballmer CEO, Microsoft was worth $642 billion, an ostensible record for an American organization that wouldn't be obscured until Apple squeaked by in August 2012. Anyhow as the Nasdaq imploded, Microsoft fell hard, and leveled out. Also stayed level.
For a decade, Microsoft's stock value has worked as an indoor regulator set to $25. What's more shareholders have a tendency to not like thermostatic stock.
Rather than fall for some great man theory of technology, it's fairer to observe that Ballmer failed not because of some obvious product flop (even though Surface stinks) or some famous design snafu (even though Windows 8 is sort of a nightmare). Instead, he failed because he inherited a company whose success relied on desktop computers stuffed with Windows and Excel. And his tenure coincided with the rise of another sort of computer mobile computers that Microsoft couldn't continue to monopolize.
The long view is useful here. Windows, along with Intel, got its clock cleaned by Apple and Google in the last decade. Their global market share of operating systems fell from 96 percent around 2000 to 35 percent in 2012. Apple and Google wedged their way into our laptops, phones, and tablets, while Microsoft saw its sliver of the mobile market decline between 2005 and 2012.