Using a firm whose sole purpose is all things IT brings a level of expertise a company could not afford to have in house.
As we witness the spectacular collapse of the Industrial Era business model, built on doing everything in-house and collecting companies up and down the supply chain to form a conglomeration, it becomes clear that something has to change. Take the old idea of using specialists to do the work, but instead of acquiring them, use them on a contracted basis. The concept behind the emerging model is to remain light and nimble. This is what SaaS can offer.