Loose Coupling with SOA

"In technical systems, loose coupling carries an overhead - not just an operational overhead, but a design and governance overhead. Small-grained services may give you greater decoupling, but only if you have the management capability to coordinate them effectively. In sociotechnical systems, fragmentation may impair the effectiveness of the whole, unless there is appropriate collaboration."

http://www.veryard.com/so/2006/04/loose-coupling.htm