[gizmo686]

The thing is; there is actually a big market for nailing two pieces of wood together; there is just no market for someone whose only skill is nailing two pieces of wood together [0]. Consider a chair where one of the cross supports got unattached. You could by a new chair, or hire a carpenter to fix it. In most cases, unless you already have a maintenance staff, you would probably just fix it yourself.

Similar with programming. If you core product is software, you should probably have an expert. However, if the software is just ancillary; you can often get by with just the basic skills.

[0] Maybe assembly lines; but with modern manufacturing technology, I doubt that is the case anymore.