Muda is the direct obstacle of flow. There are 7 distinctive types of Muda which all lead to waiting times, and therefore longer lead times in a process. Simply taking out the Muda does not work. Usually, there is a reason why the Muda is there and this reason often has to do with the other two enemies: Muri and Mura. This means there are three enemies of lean and they are interrelated, and should therefore be considered simultaneously. Instead of just looking at the traditional 7 wastes of Muda, it is incumbent to consider instead the three categories of waste used by TPS (Toyota Production System).
Take a few moments and watch this educational video.