The only number that decides whether a coat was expensive

There is a coat in most wardrobes that cost more than anything else in the room and has been worn eleven times. There is usually also a jacket that cost a third as much, has been worn every second day for four years, and nobody thinks of as an expensive purchase. The first is the expensive one. That is not a moral observation, it is arithmetic, and it is the only arithmetic in dressing that reliably changes what people buy.

The formula, and the two terms people forget

Cost per wear is the purchase price divided by the number of times the garment is worn. That much is obvious. The two terms that get left out are the ones that decide the answer in real wardrobes: care and repair go on top of the price, and resale comes off the bottom.

A wool overcoat at 1,200 that is cleaned twice a season at 25 and relined once in its life at 180 does not cost 1,200. Across ten years it costs 1,200 plus 500 in cleaning plus 180 for the lining, which is 1,880. Worn sixty times a winter across ten winters, that is 600 wearings and a shade over three a wearing. A coat is the cheapest serious thing most people own, provided it is the coat they actually reach for.

Now the other one. A dress at 480 bought for a wedding, worn twice, cleaned twice at 18, and sold three years later for 90. That is 480 plus 36 minus 90, so 426 across two wearings, or 213 each time. Both garments are in the same wardrobe. One of them is a purchase and the other is a rental with a very poor cancellation policy.

How many wearings a year is honest

People overestimate future wearings by a factor of about three, which is why the number needs to be argued rather than guessed. Work from the calendar instead of from the feeling in the shop.

• A heavy overcoat is in season roughly five months. Worn three days a week, that is sixty wearings a year.
• A tailored jacket that covers both work and dinner reaches eighty to a hundred a year in a life that involves either.
• Knitwear in regular rotation reaches thirty to fifty, and is limited by washing rather than by season.
• Shoes worn on alternate days to let them dry reach about a hundred and twenty a year, which is also roughly the point at which they want resoling.
• Anything bought for an occasion reaches between one and four, forever, whatever you tell yourself at the till.

The asymmetry in that list is the whole argument. The pieces at the top absorb almost all of the wearings in a wardrobe, and they are the pieces people economise on, because they feel ordinary. The pieces at the bottom absorb almost none, and they are where the excitement and therefore the money goes.

The garment you are bored of buying is almost always the garment you should be spending on.

What a low number is actually worth

Below about five a wearing, price has stopped being a useful signal and the only sensible questions are whether the thing fits and whether it will survive. Between five and fifteen you are in the normal range for good clothing used properly. Above thirty, you have bought an event rather than a garment, which is a perfectly respectable thing to do as long as you know that is what happened.

The number also tells you where to spend on care. A coat at three a wearing justifies a proper brush, cedar hangers and a relining at year seven. A dress at two hundred a wearing justifies nothing at all, because nothing you do will move a number that large.

The fourth of something

There is a reliable pattern behind most bad purchases, and it is not extravagance. It is buying the fourth of something you already have three of. The fourth navy jumper does not add forty wearings to the wardrobe, it takes ten each from the three that were there, and the cost per wear of all four collapses at once. Meanwhile the coat you own two of does the work of six.

This is why the honest version of the calculation is marginal rather than absolute. The question is not what this garment will cost per wearing. It is how many wearings this garment adds that would not otherwise have happened, and which existing pieces it is about to take them from.

Where the arithmetic stops

Cost per wear is a tool for the middle of a wardrobe and it fails at both ends. At the bottom it will happily recommend something cheap and unpleasant that you will wear a hundred times while disliking it, which is not a good outcome. At the top it cannot price the piece that is worn twice a decade and matters enormously on both occasions.

So use it where it works, which is the eighty per cent of a wardrobe that does the daily labour, and leave it out of the room for the two or three objects that are not really clothes at all.

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