Whenever we talk about an “old theory” that has been displaced by a newer theory, we often mock those who held the “old theory” because of how wrong they were. We laugh at the geocentric theorists, and we laugh at the heliocentric theorists that displaced the geocentric theorists. We cleverly know that neither the Earth, nor the Sun are the centre of the universe.
It is important to admit, though, that most of us would not have worked this out alone.
It is also important to understand that each theory is a fundamental step towards our current theory; and the current one will one day be displaced just as easily as all those that went before. It simply isn’t possible to leap from no theory to a perfect theory. It is, though, eminently possible to work within a theory, find its limitations, and use those limitations to discover the next theory.
For example, this tenous metaphor may illustrate the point! If I want to drive to a place I have never been, I will enter the address into a popular maps application and it will guide me to the destination. When it announces that I have arrived I often find that I’m not actually at the correct address and need to look at door numbers as I continue past the predicted location and find the exact spot. I managed to find the correct location far better than the mapping application… but I wouldn’t have done so if it were not for the direction supplied by the app in the first place.
And the same goes for management theories, and software development theories. We would not have arrived at our current preferred method had it not been for the previous methods. So while we may mock Waterfall… we might not have progressed without it. Pay homage to the old theories as they are fundamental to the newer, better ones.