So the analysts are saying computers are going to decline in volume shipments this quarter, for the first time in ages. I'm not surprised. The circumstances are probably worse for the IT industry than they were last time this happened, in 2002.

The people who make these things have made computers that work. That was, on reflection, a bad move.

Think about it. In this report the BBC quotes people saying that replacement computers, if they slow down, aren't the same priority that they would be if the economy were doing better.

Maybe. But I can't help noticing that the iMac I'm using at the moment is working fine, almost as it did on day one. It works. And even more unusually for a 15-month-old computer, it's a current model.

This is good for me. It's good for Apple's reputation, and I know other manufacturers are churning out boxes that are equally reliable. But even if the economy were zipping along like anything I don't think I'd want to replace it - there's no need. This is lousy for Apple's bottom line.

And this is where computer makers are going to struggle even when the world economy recovers. People have become wise to buying systems that only just cover their needs, they now want more because they see their needs will change. And they're buying accordingly, then not upgrading for years.

It's wise purchasing, that's all. And it's going to hammer an industry that was reliant on either organic growth (forget it, the installed base is now established) or upgrades for its viability very hard indeed.