It's actually "accountability" that's a big part of the problem.
Government procurement is so focused on the appearance of fairness and money saving that all other goals, like actually getting something that works, take a back seat.
You end up with over-specified requirements that remove the possibility of innovative or creative solutions. Providers are treated like a commodity, where it is assumed that all will do the same job, and cost is the only real negotiation point, maybe with some kind of scoring grid against the over-specified requirements thrown in.
And the procurement decisions are made by procurement officers who are not the actual users of what is being bought (in the name of objectivity).
So what happens, on a good day, is that the operational users in the purchasing department work with the preferred vendor to "wire" the RFP to reflect the scope or work that is wanted and add requirements (e.g. years of very specific experience, past projects) that heavily favor the preferred vendor. At least this way the department may get something they want, thought it obviously can be gamed. Worse though is that many contracts just go to lowest cost staffing firms that are optimized to comply with government procurement requirements and provide the minimum set of bodies that meet those requirements, usually former government folks rented back, plus some low cost IT resources, that are there to execute to the letter of what the government has over-specified, usually something that wont actually work as written.
This is why so much government procurement is a failure by any objective measure. What I have seen work is when a vendor provides a credible unsolicited pitch to a known problem at a fixed cost, and the relevant departments are forced to decide if it makes sense.
In Canada we had a major one like that a few years ago, the outcome was great for the department that needed it, but careers were destroyed in the process as politicians and their incumbent friends pushed back to try and stop it.