While Mr. Ballmer, who has been at the helm of Microsoft since 2000, is known for his eccentric personality and episodes of excitable public behavior,he gives sound and structured advice to business leaders about how he approaches his work at Microsoft.He says that there's a stereotype that innovation happens at a rapid fire pace,but he doesn't agree-he thinks that companies should invest in innovation over a long period of time.Hardly anything in the tech industry went from rags to riches overnight, he explains.And while talking about and emphasizing a culture of innovation is crucial for a company's success, he says, there must be a limit when a company reaches a larger size.Cultures of innovation don't mean that everybody gets to reinvent the wheel six times.The need for a certain level of persistence and tenacity is I think a surprisingly important part of innovation.And when it comes to making decisions, he'd rather not have to do it very often, but instead thinks a leader should delegate as much as possible,rather than running a company that has to come to him for every single one. While he does make the big choices,such as whether or not Microsoft will invest with a certain company,and will sign off on decisions that other people have made, the number of decisions that I actually have to make myself is relatively low, he says.