My partner and I consult with a variety of firms on the topic of cloud adoption. It is surprising how few really understand the strategic and ROI benefits of its application. Total Cost of Ownership is an important number to use when evaluating IT and in particular when comparing extant systems to cloud solutions. Often the thinking is that what an organization is using now is a better place than making a change - and the primary driver in most people's minds is cost. Utilizing TCO is the only way managers can evaluate apples to apples. Often there are apples to oranges comparisons and this is why more organizations aren't jumping into the cloud faster. They simply aren't doing the proper math to realize the savings.
Use this interesting evaluation tool. See what your organization is missing by not embracing the cloud.