BPM systems provide the same infrastructure capability as an RDBMS, but applied to application processes rather than simply data.
"The reason people are thinking of and implementing BPM is that they face a host of process related issues. That's similar to what happened with data because it all became embedded in applications, and people said there had to be a better way of managing the data. But now applications have become the problem, with business process fragments locked away in stovepipe applications, and people want a better way to manage end-to-end processes. The IT litter across the organization has become so voluminous that people are looking for a way to renormalize it and put it into a standard form."
