Some savvy advice here, covering the bases. So, more for my own sake, and in the context of sales, here are my notes as to why "people" might be the "weakest link" in a BPM project. Well, actually I don't believe that "people" are the weakest link . . .
1. BP GOVERNANCE -- Is business process defined, owned and managed in the framework of normal business? Often not. And any attempt to bridge hidden fissures in the organization with BPM will expose organizational weakness. Which can often come out in analysis and be "blamed on people".
2. RATIONAL RESISTANCE -- However grumpily expressed, it is quite possible that resistance to an ill-conceived BP project is rational. The analysis sessions are seen as vacuum cleaners of the mind, without reward. Experienced staff may believe that the organization will be the worse for the project, especially as tacit knowledge may be ignored; of course staff may also fear for their jobs. Again, "people" get labeled as a "problem", when in fact they may be acting rationally, both on their own behalf, but also quite possibly on behalf of the organization.
3. UNDERSELLING BUSINESS PROCESS -- If business process is sold as just another kind of software (last week it was a JAD session, this week it's BPM), then an opportunity is missed. BPM.com exists for a reason, because of the central importance of business process. No one gainsays the effort required to master accounting, and that accounting is central to any organization, and especially that training and study and practice are required to master accounting. BP is still years away from definition and acceptance as a "profession" like accounting, if it ever achieves that status. Nevertheless consider what is expected of a business process project or program: that whole parts of a dynamic organization will be modeled and defined and evolved using the technology and principles of business process management. That's a tall order. For the team tasked with the work, it's "game on" and no half-measures. Some of the problems concerning BP governance and rational resistance to a BP initiative can be overcome if the team catches the excitement of what they are about to embark upon. Not all teams or organizations will be able to do this, for sure.