Add a Third Axis To Greiner Model
This model is based on the time where there is no end for the time. How a company knows the moment for it to move from a phase to another?
The Greiner's model can be enhanced by adding a "Z" axis defining the organization evolution over the time. In others terms, we could have the "X" for the time, the "Y" for the organization size and the "Z" for the organization evolution over the time (1 year for instance)
I think that this will allow the company to fine-tune with their strategy.