There is a significant amount of evidence, collected over many years, that departments and agencies struggle to maintain a sense of proportion when it comes to major projects and procurements. One example of this problem is the temptation of ministers and civil servants to set unrealistic timescales for large procurements. Another is the practice of signing legally-binding agreements when the tasks which the contractor will be required to perform have not yet been resolved.
These are fundamental failings, and they have been often identified by the NAO and other government inquiries over many years. Their recurrence in major contracts in recent years should be a matter of grave concern to government.
To some extent, this is the problem of optimism bias, now well-recognised (although not always overcome) in the planning and execution of major projects. But there is more to it than that - it seems that the adversarial nature of the procurement process and the creation of a strong organisational boundary between commissioner and provider also plays a part.
When it is done well, contracting obliges commissioners and delivery agents to clarify the intended outcomes of the service in question, and the resources (people, money and time) that will be required to deliver those results. This is the core principle on which the discipline of commissioning has been built - commissioners are not only given a range of levers to ensure that the hand-off from policy (and funding) to delivery is managed well, but they are also provided with a place to stand. It is as much a question of authority as it is of capability.
When commissioning and procurement are done badly - in circumstances where there is only weak authority or incentive to challenge - the contractual boundary serves to magnify the self-deception (on both sides). And of course, in a market where there is little trust and where both sides are gaming the system, the boundary becomes a conflict zone. This is not primarily about the public-private divide, but rather an extreme version of the traditional differences between policy and delivery.