Commercial considerations
Stigmergic systems have to be financed. They have to exist in a highly competitive commercial world. It doesn't matter how clever a system is, if it doesn't meet the stringent requirements of these two all-important considerations the project will fail.
The highlighted links on the left point to articles that will provide a basic understanding of financial and commercial strategies. Even if your interest is only in the research or technology side of stigmergic systems, this is essential prior knowledge.