Marks & Spencer: Your average customer does not look like Rosie Huntington-Whiteley

I once knew a woman who worked at Marks & Spencer and was told off by her store's manager for wearing the wrong sort of nail varnish. The colour was "inappropriate" for their working environment, he said. "It is this store's best-selling shade of M&S-brand nail varnish," she told him, wanting to add, "and as the manager of this store you really ought to know that." I think of her every time I hear that Marks's profits have fallen, again, thanks to nobody in charge being able to figure out what sells.

So it was last week, when M&S announced that its pre-tax profits were down by 9 per cent, with sales of general merchandise (which includes clothing) down 1.3 per cent. The company's bosses have blamed everything, from rival shops to the unseasonably warm late summer. When is somebody going to tell their desperate chief executive Marc Bolland that it's not the wrong sort of weather that is letting M&S down but the wrong sort of clothes?

Here's the thing, Mr Bolland: me and my mum and most other women between the ages of 30 and 90 can walk through our local M&S and immediately point out which items won't sell and why. Here are some clues: that nice checked shirt you had in recently would sell … if you hadn't panicked and added that ridiculous frill at the last minute. That nice blue/brown/grey top would sell … if you hadn't stuck an acid yellow splash across the front. British women don't tend to look good in acid yellow, not even in an unseasonably warm late summer. In fact, you know that fashion rule about looking in the mirror before you leave home and taking off the first thing that catches your eye? You should apply it to your designs.

Underwear would sell if you made it out of cotton, not polyester, and if you didn't show us a big poster of what Rosie Huntington-Whiteley looks like while wearing it.

Your average customer does not look like Rosie Huntington-Whiteley. Your average customer looks more like Nick Clegg, who, coincidentally, admitted last week to buying his underwear in M&S. (Does the Deputy Prime Minister wear polyester pants? We should be told!)

Many more clothes would sell if you had them in shops in the right sizes. When you notice that, say, the High Street Kensington branch in London is always out of size 10s and 12s, here's an idea: stock more size 10s and 12s. Don't just hope that Kensington women will get fatter.

Shoes would also sell if you kept more than a size four in stock, and to suggest customers "order them online" is no use to those who hope to leave an actual shop with an actual pair of shoes on the day that they actually go shopping.

Mr Bolland is welcome to borrow my mum if he wants to walk through his local M&S one day and hear her spookily accurate predictions about what kind of clothes women want to buy.

But here's an idea: maybe M&S should appoint some bosses who know that, too. Like, for example, some women.

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