The recession has coincided with a fashion for false apologies.

Bankers and the like have been saying sorry for their mistakes with all the sincerity usually associated with a confession at a Stalinist show trial or a recantation before the Spanish Inquisition.

Yet there are some admissions of error that do strike the right note.

In reporting Berkshire Hathaway’s worst year since he became Chairman, Warren Buffett said, “During 2008 I did some dumb things in investments”.

Is such brutal honesty a good thing in business?

In general, no: it pays an entrepreneur to be positive. You get no credit for sharing your worst mistakes or fears with others.

However, there comes a point when problems are so obvious that to attempt to conceal them destroys all credibility.

That is the moment to be frank. The trick is choosing that right moment.

It also helps if, like Mr Buffett, you have built up a reputation for plain-speaking and fair-dealing over many years. Unlike the bankers, he did not have to be forced into saying what he said – most of his investors know he probably would have said it anyway.