How could Digital's collapse be so precipitous? It's because, in many ways, financial performance data is misleading. As you move up to the top of the market, you're getting rid of the less profitable products at the low end and adding business with more attractive margins at the high end. The rate of unit volume growth might be tapering off as you pursue these smaller markets, but your margins actually look better. So Wall Street rewards your stock price until you hit the ceiling.

The biggest mistake is an over-reliance on data. Managers will say if there are no data they can take no action. However, data only exist about the past. By the time data become conclusive, it is too late to take actions based on those conclusions.

There are direct paths to a successful career. But there are plenty of indirect paths, too.

Another thing I've observed is how critical the role of the CEO is when a technology truly is disruptive. In looking back on companies that have successfully launched independent disruptive business units, the CEO always had a foot in both camps. Never have they succeeded when they spin something off in order to get it off the CEO's agenda. The CEOs that did this had extraordinary personal self-confidence, and almost always they were the founders of the companies.

Lets take the best of our ideas from Global Drucker Forum, and the best of our language, and then focus and clarify.

Watching how customers actually use a product provides much more reliable information than can be gleaned from a verbal interview or a focus group.

My conclusion: Management is the most noble of professions if it's practiced well. No other occupation offers as many ways to help others learn and grow, take responsibility and be recognized for achievement, and contribute to the success of a team.