Back when I was an IT Manager for a major company, I heard many around me screaming that we needed a cloud presence. "Go to the cloud, ditch our expensive data center," was a common mantra. Then my team investigated the costs. What we found has been partially corroborated in this article.
If you already have a data center, going to the cloud is expensive, and moving TB of data back and forth is very expensive. I remember my boss and his boss weren't too happy to hear that news. They had heard the cloud was cheap, and it is compared to green fielding your own data center, but if you already have one, use it.