G4S promised 10,000 or so trained guards and last week admitted it would be nearer 6,500, which meant the armed forces would have to plug the gap.
Shambles do not happen by themselves, you see, so I expect he'll say part of the reason for this is that there is a hyper-shambles a bit higher up.
Because originally, G4S were asked to provide 2,000 trained guards. The remaining 8,000 were going to be volunteers and college students.
That was in 2010, and about six months after the contract was signed the security services raised the national terror threat level which most of us could work out would probably mean security needed to be tightened up.
But it took another six months before the Home Office figured this out and the security services explained that volunteers and students would not cut the mustard.
So in December 2011 it was decided that we needed more than 23,000 guards, which would need to include 7,500 military, 3,300 volunteers, and 10,400 G4S trained personnel.
Added to which the guards provided by G4S were supposed to pass some strict criteria set by the Home Office - they had to have a five-year checkable history, speak good English, and either already have or be able to qualify for, security industry accreditation.
In return most would be paid between £7 and £9 an hour, a rate an accredited guard could easily triple working in the same job for someone else.
And we were going to need it all within six months.
Unsurprisingly, and as a blind man could have seen a year ago, the security operation got all cocked up. They couldn't find enough people meeting very strict rules prepared to work for peanuts, and didn't mention this would be a bit of a problem until a fortnight ago. Now more soldiers are being pulled off leave, police officers are being called in, and even those signed up to work for G4S have started to disappear.
Around 300 guards were expected to arrive at Box Hill in Surrey yesterday to guard it in preparation for the Olympic cycling events; 40 turned up. Fifty eight were scheduled to be on duty guarding teams at the Hilton hotel in Gateshead, but only four arrived and one of those later disappeared. Undercover journalists who have signed up to the security courses in the past few weeks have found 'guards' who can't speak English, fall asleep, or are due in court. The ones who have made it through, and the volunteers, wonder how they're going to get to work for 5.30am starts when the Tube doesn't start until after that and they're not allowed to park at the Olympic sites.
So it's all a mess, not just because G4S have been rubbish but because the people telling G4S what they wanted got it all arse-about-face and, when they should have realised a year ago that wasn't good enough, didn't fix it or keep more of an eye on what we were getting for our money.
The cost today is £284million for those 13,000 guards, a number of whom don't seem to have bothered turning up. On top of that is almost as much again for the cost of police and soldiers who aren't doing other things, and the MI5 officers for whom all leave has been cancelled, and even though G4S are being fined it won't make much of a dent in the cost to the taxpayer.
And above all this is an omni-shambles, in which games organisers LOCOG won the right to stage the event in 2005 and were so busy wetting their pants they stopped thinking.
They allowed the £2bn cost to spiral to £9.4bn by 2007. When the financial crash came in 2008 they didn't scale back their plans or wonder if they needed quite so many BMWs. When the government changed in 2010 and a massive programme of austerity cuts was introduced they saw no reason that "we're all in this together" should include their sports competition. When recession continued through 2011 and we went into a double-dip Seb Coe didn't think it would be a bright idea to go over the spending and make sure we were getting what we'd paid for.
And the reason those things didn't happen is that even further up, right at the top, is an overarching meta-shambles being woven by three blundering twonks whose hamfisted handling of all the problems on their desks, whose shonky maths, unprincipled politics and slimy denials of the bleeding obvious make G4S look as efficient and well-oiled a machine as the T-1000.
Yesterday Cameron and Clegg announced they had achieved more in two years than the entire governments of Thatcher and Blair over a total of 30 years.
Well, they have, if you count Olympic-level bungling as an achievement.
It's these three unwise monkeys who have cut police and armed forces numbers, just when we need them to stop the Olympics being blown to smithereens. They reduced the size of the welfare state just when more people needed its help because the money's all gone. They made 32 budget u-turns, upset every nurse and GP in Britain and failed to lift us out of recession. They have denied a judicial inquiry into the ethics and practices of the banking industry, which made Cameron and Clegg's family wealth and did Osborne no harm either but has done the rest of us few favours.
Thanks to their efforts during the past two years, most natural Liberal Democrats in Britain - teachers, nurses, clerical public sector staff, lecturers and students - loathe Nick Clegg.
Most natural Tories - those running small businesses, manual workers, the aspiring middle classes - loathe David Cameron and George Osborne. Even the bankers whom they have done so much to protect, fighting at every stage a small tax on financial transactions which could raise billions from the City, are starting to back away from people whose idea of achievement is writing a press release about it.
It's all very well getting the head of G4S in to explain his bit of the "humiliating shambles". But that's the same as asking the winner of a school sports day three-legged race why he's not on the podium taking gold in the 100metres. What about the rest of them?
Get Seb Coe in there. Labour politicians who from 2005 thought the Olympics was so far off they didn't need to bother keeping an eye on things. Get the Home Secretary, the civil servants who negotiated the G4S contract, the bureaucrats who drafted laws permitting censorship of free speech, the politicians who were expected to scrutinise and instead wangled free tickets for themselves.
Of course if we did that we'd be here all year and the rest of the world would realise everyone involved in running this country is an incompetent wet fart who couldn't run a tap, never mind a race.
No, the best thing to do is moan about the shambles while ignoring the hyper-shambles, the omni-shambles and the great big meta-shambles, and hope like hell that if we do that then no-one else will notice it either.
I'm sure everything will be fine.
Just when you thought it was safe to go back in the water...