Economics is a difficult question
If it wasn't, we'd be able to forecast it properly, instead of only being able to sometimes find a reason after the fact.
I find this article quite interesting, but I can't help having a bit of an issue with the premise of billions not guaranteeing a return.
Amazon, Google and others have thrown billions into making data centers and the result is showing : Amazon is apparently better off than Microsoft when it comes to cloud services.
Cloud services are not summarized by the services you offer to your customers. You can have the greatest list of features on the market, if your cloud is down regularly, people will go for alternatives that may offer less features, but are more stable.
Stability is what costs billions. The backend requirements for ensuring proper response times and failover is something that is quite beyond me, but I'm quite sure that, in terms of hardware, bandwidth and server monitoring, it must absolutely mind-boggling. Experience in this domain is capitalized upon, and cannot be just bought.
So I do not see newcomers having the slightest chance at upsetting the establishment. Very, very deep pockets are required to enter this market, and when you're in, you still have to learn how to make it work the hard way - meaning losing customers every time you fail to maintain stability.
There are three big names in the enterprise cloud space at this time : Amazon, Microsoft and IBM. I'm pretty sure we won't be adding many more to that list.