In most cases, this is simply a question of incompetence - it certainly is in mine. However, it is also true that the most exacting professionals fall to bits when it comes to their own homes. A friend of mine used to live with a very successful electrician. "There were all these wires hanging from the ceiling, " she recalls fondly. "He used to say, 'It's fine, it's fine.' And he also used to say, 'Don't touch ANYTHING'."

After a long day poking around in someone else's wiring, it is of course understandable that the last thing you want to do is poke around in your own. And once you have redecorated the living room four times and got varnish fingerprints all over the television set, the heart does seem to go out of you, at some profound decorating level. But it is hardly arguable that our obsession with home décor has passed. It's more a matter of simply shelling out the cash.

In life, you have to learn to live with your mistakes. In home décor, this does not have to be the case. As I write, I am looking at the paint lapping over the door handle of this room - I went a bit wobbly when I was painting it - and it is still there as an admonishment, years later. Meanwhile, in the same room, a professional painter failed to cover the area behind the radiator and I couldn't care less. For this and other reasons (well, the other reason is constant arguments about the colour), the bathroom still hasn't been painted old white, vibrant yellow or baby blue.

(Believe me when I tell you that it was never going to be painted baby blue.

Baby blue was just a negotiation stance. ) But painting is the easy bit, really, once you've found your colour, tried to unblock the painters' chalk and gone to a couple of work meetings with magnolia in your hair. It's the actual fixing and building of things that is really tricky. Shelving and plumbing and sanding.

In DIY, as in drug taking, confidence can get you into a whole lot of trouble.

Without naming names, there are people in this world who will happily approach a plumbing job without actually knowing where the stop-cock is. It can take a couple of very soggy minutes to locate a stop-cock, a search which can involve turning off the hot water, the heating and lots of other vital household utilities which have never returned at all.

And once the stop-cock crisis has passed, and has been mopped up, and the story has been told several times to friends who couldn't care less, everyone is exhausted and far too tired to complete the task they set out to accomplish in the first place.

The only happy DIY house is the one where the female is in charge of DIY.

There are competent females like this, who have their own tools and only get shirty when their husbands insist on helping out. The phrase 'I'm quicker on my own' originates, not in the kitchen, but in female DIY. These girls light a fag and get on with assembling the flat-pack stuff when the children are in bed.

Away from such happy homes we have to blame television for showing us what can be achieved by three carpenters and a lot of very heavy editing - and then implying that we could do as much ourselves. The DIY RIP programme was presented by Carol Smillie, who once fronted Changing Rooms. Changing Rooms and programmes like it sent hospital admissions soaring, as gullible viewers stapled their hammers to their knees, and then decided that they did not want to live in a living room that had been re-styled as a New Orleans brothel after all. In this way, Changing Rooms and its Irish imitators probably started the influx of Polish workers into this country - good plumbers and painters who would actually turn up. Enda Kenny, with Celtic and Christian remarks, should take a good look at this one.