Chanting Odaimoku is not an activity of quantity but of quality. We should be thinking of how much of our lives we can fill with Odaimoku and not how much of our time. I will not say it is wrong to chant fast, but I will say it is wrong to chant sloppily, lazily, or distractedly. Yes, we may loose our focus at times; we may feel the tug of day-to-day life and distractions. This whole chanting thing is meditation and so just as we do when we are in silent meditation we do when chanting, which is to come back to the present and return our focus whether it is breath or Odaimoku. But if we start out in a rush, in a hurry, or with mixed objectives then it will be more difficult if not impossible to move to a more deliberate, contemplative practice that allows us to nurture and absorb the benefit of the Lotus Sutra.