It's common to all large organisations. Because large organisations get like this; if everyone does their own procurement then money gets misused, wasted, and becomes uncontrolled. So they centralise procurement, and that disconnects it from the people who understand what they're buying, so they have to control it through process, and the process bloats until we get to this point.

One of the many, many, arguments for not allowing organisations to get this big.

Because corruption is a thing. Also: any government contract can be audited at any time by the National Audit Office, who have criminal prosecution powers if they find malfeasance in the procurement process. Also: being hauled in front of a Select Committee to answer questions about a given procurement is not fun. Also: politicians are always looking to ask questions that get their names in the paper.

Follow the processes. Document everything. Make certain the winning bidder has all the relevant certificates and insurance covers in place before agreeing to anything.

Leaving the Civil Service was one of the best work decisions I ever took.