Andrew Smith has a great post on the 5 reasons that organizations of 200-300 people fail to implement BPM. Of course there are many reasons, but these are pretty good.? The biggest reason that I've seen: budget.? It isn't that there isn't ROI for these projects, but the ROI still requires the "I" to be paid, largely up front, in terms of implementing the process they need.?? Often the folks within these organizations that have the need for BPM and the knowledge and drive to pursue it, simply don't have a budget that let's them go after it.
However, with the advent of more and more SaaS and open source offerings, and more "rent" than "buy" models becoming available, even within the BPM space, companies of this size will find the up-front "I" in their ROI equation may be declining - so they don't have to take the same budget or cashflow hit to achieve the results they want...? So perhaps going forward the other issues Andrew mentioned will dominate.