Key point inevitably overlooked
Various commentards have correctly pointed out that rail privatisation is widely regarded as a failure because the rail system continues to receive massive public subsidies, while services don't improve.
But the same is true of all the utility privatisations. Public subsidy may not be so clearly evident, but it certainly delivered in spades via the welfare budget. Most people who are in receipt of benefits (NB not just the unemployed, but also the tax-credited, the winter-fuel-allowanced etc) use a substantial chunk of those benefits to pay their water, gas and leccy bills. The big difference post-privatisation is that this money is now flowing into the back pockets of the privatised company's executives and shareholders, instead of back into the public coffers. The privatised utilities are deliberately configured to siphon money from the taxpaying public to the corporate elite.
For those reading the news, the same dynamic is very much at work in Cameron's stated plans for cutting the welfare budget. In his fundamentalist monetarist zeal, he overlooks what nobody mentions but every sensible person knows - that the main objective of tax credits which subsidise the low-paid is to enable their employers keep wages unrealistically low. This keeps costs down and profits up - so tax credits are really just another subsidy paid by the taxpaying public to the corporate elite.
It's a well-worn axiom of every TV cop show, but it's true - if you want to know why stuff happens and who is making it happen, you follow the money.