Making real, high-level continual improvement is more of an issue than the speed of improvement.
Juran illustrated this in his "spiral of progress in quality" concept. To simply restate the concept, as organizations take action to make improvements in their products and processes, the performance and success of the company spirals up. Each completed improvement action is a step up a spiral staircase. Each additional improvement builds upon the previous one to take the organization to higher levels of achievement. This is a very powerful and effective quality improvement approach.