Kinda what we all thought....
Having been, in the past, involved in both private and government dept IT projects as a senior tech i can, with my hand on heart, say that i never expect ANY govt project to be completed on time, on budget or work the way it was originally intended. (As for private companies, i'd say about 70% achieve, give or take a little, the goals set).
In my experience, the reasons are simply, and as has been said above, that totally unsuitable people are hired or placed at the helm of these projects and there is insufficient understanding of the complexity of issues leading to major changes to the project goals when the project is already underway - most often making the work already done worthless.
I am not totally against non IT people being Project Managers, as i know some who aren't IT folks and are very good PMs, but they do know their technical limitations and do not become 'yes' men or women without getting a solid enough understanding of whether something can actually be done or not. Unfortunately, the mindset within govt that i have seen relies on the shared blame culture and the underlying concept that if more money is needed then the govt will simply give more.
And as for the headline, as we have all heard before about a 'Skills Shortage'...well, that is absolute rubbish. There are plenty of adequately skilled and motivated people who could do the job to a very good standard. However, they don't get a look in because of the closed shop mentality of govt giving jobs to existing staff or their friends/family regardless of experience, the pay is not as good (although the benefits of not being sacked for being useless and a final salary pension scheme are attractive) and finally, a lot of good people are leaving...or have already done so.