I've been in the Navy for over eight years now, and much of how the military purchases equipment doesn't make sense in the real world. For example, there are many instances where Commercial Off The Shelf (COTS) products are used, and this is fine for most products.
However, when it comes to computers & high tech devices, quality goes up and price goes down rapidly. I've seen instances where a multi-year computer contract is signed that pays for high end systems, and locks that initial price in for additional and replacement units. The problem is that the price of a specific computer model will drop to about half in a single year and be worthless in three, while the Navy will continue paying the original purchase cost for now obsolete replacements five years later.
Also, there are specialized equipment systems where the final purchase authority doesn't have more than a conceptual idea of the system, i.e. s/he knows what the system does, but doesn't know the details of the individual pieces of gear within the system and how they interact with the whole. This leads to contract padding, where a system is made unnecessarily complex in order to increase the contract cost. If enlisted maintenance technicians & installers were more involved with the final purchase it could result in a better and less costly product.
More examples can be given, but this post is long enough as it is.