From Jeff Randall in the Telegraph, a piece on the carnage of DIY over the Easter weekend.
The curse of DIY is inflicted on us by two policies: income tax and trade credential regulation.
The income tax is obvious: There is a job in my house that will take a skilled person an hour. I have two choices: I can do it myself, or I can work for money with which to pay someone else to do it.
Assume I get paid the same as a skilled tradesman. I have to work for an hour to pay for an hour of his time. Then I work for another 40 minutes to pay his income tax. Then I work for another 17.5 minutes to pay the VAT. Then I work another 78 minutes to pay my income tax. In the end I have worked three and a quarter hours to get an hour of someone else's time. The temptation to think I can do it myself in less time than that is very strong.
The credentials are the other problem. The costs of getting a professional are inflated by rationing the supply.
It can be argued that the regulations are necessary to protect from under-skilled practitioners. But that assumes that the result of banning the less qualified provider will be that a more qualified one is used. The facts of DIY show the fallacy of this - if I can't hire a cheap workman, I'll probably have a go myself, with worse consequences.
It is like the ever-increasing monitoring of the quality of parents. I have seen at quite close hand the struggles of the underqualified single parent attempting to keep her child out of the clutches of the state. The process could possibly be justified if the end result was giving the child a better home, but in reality the only alternatives are the foster system or a children's home. The most stringent sane criterion for judging the adequacy of a parent is whether she is doing a better job than the children's home would, and the most stringent sane criterion for judging whether a workman should be allowed to do a job is whether he would do a better job than his potential customer.