My (Our) practical experience NOT just an opinion - of course, this post is not meant for experts who neither believe in forecast accuracy nor in measuring or creating point forecasts.
Repeatedly our best ROI has been on the clients who have belonged in the class 25% - 50%. With diligent effort across the board, we have been able to lift this group to 70+ and a couple of our clients over the 85% threshold.
The effort includes -
* Refine the process
* Understanding the purpose of forecasting and identify where NOT to forecast or mess with
* Implement the process/tool to create a good Statistical baseline forecast
* Revamp the organization to hire the right skillsets
* Training on the process and the tool
* reinforcement on a monthly basis to both evaluate the Stat forecast as well as the Demand Consensus process
I would say this group (25-50) is the sweet spot - because so many simple things are messed up. It would be amazing to the external eye how much basic stuff is missing - how common sense becomes a rare commodity when your back against the wall with the everyday "busy" stuff.
How simple? - you will typically see a straight line forecast in the system when the data shows a clear pattern.