That's exactly it; it's down to the NHS not being prepared to pay for quality - nothing to do with the free market at all. The market can provide good quality cleaning, after all private hospitals manage it well enough. If the NHS spent as little on employing their own cleaners as they do on employing external ones the results would be just as bad.

NHS buying policy is like doing all of your shopping at Netto - it's cheap, but that's all it is. The market provides options, including quality ones - if you want it you can get it, but you're going to have to pay M&S prices.

The only difference between not spending enough internally and not spending enough externally is that the latter allows the people responsible to pretend that it's not their fault.