I think that there's a certain wishfulness bordering on naïveté to this pursuit. We tell ourselves that we are managing complexity by having small, well-tested units that are reused by an entire community. But software complexity continues to exist. We think we are mitigating the complexity of our own software. But the complexity really just shifts to the integration of components.

Anyone that has been around long enough has war stories about getting two relatively simple pieces of software working with each other. In my experience, integration problems are often the most difficult to deal with.