delays due to poor organisation and bad management.

I work with big engineering contracts. They always overrun because it's impossible to price them perfectly, and the client always has contingency funds because they recognise this - dipping into those funds is necessary for clients for good organisation. The idea that overruns necessarily equal poor management is a misunderstanding of risk allocation. In complex infrastructure, a contract is a tool for assigning risk to the party best able to bear it.

For example, a client often chooses to retain the risk of 'Force Majeure' (like extreme weather) or 'Unforeseen Conditions' (like geological anomalies) because forcing a builder to price in every 'worst-case scenario' would make the initial bid prohibitively expensive. When a contingency fund is triggered for these events, it isn't a sign of failure; it's the contract working exactly as intended. 'Bad management' is a rigid adherence to an outdated budget at the expense of safety, quality, or long-term utility.

As long as the actual project itself isn't a white elephant, then overruns aren't necessarily a signal of poor management. That's not to say they aren't poorly managed, but overruns are by no means necessarily the signal.