Their "assumption" for hardware purchase prices seems way off compared to what we buy from Dell or HP.
It's interesting that the "IT labour" cost they estimate is $140k for DIY, and $120k for Azure.
Their saving is 5 times more than what we spend...
Even so, a rough configuration for a 2-processor 16 core/processor server with 256GiB RAM comes to $20k, vs $22k + 100% = $44k quoted by MS. (The 100% is MS' 20%-per-year "maintenance cost" that they add on to the estimate. In reality this is 0% as everything is under Dell's warranty.)
And most importantly, the tool is only comparing the cost of Azure to constructing and maintaining a data centre! Unless there are other requirements (which would probably rule out Azure anyway) that's daft, a realistic comparison should be to colocation or hired dedicated servers, depending on the scale.