Most product-development managers are always struggling to bring in projects on time and on budget. They never have enough resources to get the job done, and their bosses demand predictable schedules and deliverables. So the managers push their teams to be more parsimonious, to write more-detailed plans, and to minimize schedule variations and waste. But that approach, which may work well in turning around underperforming factories, can actually hurt product-development efforts.

A version of this article appeared in the May 2012 issue of Harvard Business Review.