Some of these comments seem, perhaps indirectly, to back up a theory I've pondered for a while:
Would procurement be such a mess if people at the top were responsible for projects for longer - maybe even right from the beginning up to the point whereby it's received its RTS?
As an outsider looking in, it seems that every time the reins are handed over the goalposts get moved, leading to inevitable cost and time overruns, which then get exacerbated further another few years down the line. Of course, some of these goalpost moves could still happen (real world changes etc) and it probably wouldn't help if the right appointment wasn't made to begin with, but surely we'd be in a far better position than we currently are?
