A coat is bought in twenty minutes and worn for a decade. The arithmetic is unusual. Few other garments are chosen so quickly and judged so often.

Most coat decisions go wrong in the same way. The colour is right, the price is acceptable, the mirror in the shop is flattering, and nothing was checked that actually determines whether the coat survives three winters. What follows is what to check, in the order it matters.

The coat is the most-seen garment you own

Count the hours. From November to March a coat is on the body for every arrival and every departure, in every corridor, on every platform, through every meeting that begins before it comes off. The shirt underneath is seen by a handful of people in a single room. The coat is seen by everyone else.

This changes how the money should be allocated. A wardrobe that spends evenly across its pieces is a wardrobe that has not noticed where it is being looked at. The coat carries more of the silhouette than anything else in the winter months, and it carries it in public.

It also changes the standard. A coat that is merely acceptable will be merely acceptable four hundred times. There is no quiet corner for it to hide in. The argument for buying fewer and better applies here more sharply than anywhere else in a wardrobe, and it is set out at length in dressing less and choosing better.

So the question is not whether a coat is nice. The question is whether it will still be right in its sixth winter, when the novelty has gone and only the proportions remain.

Shoulder fit first

Everything begins at the shoulder. It is the one part of a coat that cannot be altered without rebuilding the garment, and the one part that decides whether the coat reads as made or merely bought.

The shoulder seam should sit at the edge of your own shoulder, where the arm begins to turn downward. Not beyond it. A seam that falls onto the upper arm collapses the line and adds width where nobody wants width. A seam that sits inside the shoulder pulls across the back and will not close comfortably over a jacket.

Check it with the arms down and then with the arms forward, as though reaching for a door handle. A coat that binds across the upper back in that second position will bind every day. Diagonal creases running from the shoulder toward the opposite hip mean the shoulder is too narrow. Soft folds hanging below the seam mean it is too wide.

The Coat 01 is cut with a shoulder that sits close to the natural line rather than extending past it, which is why it holds its shape over knitwear without turning square. Where a coat is going over tailoring rather than a jumper, the Coat 01 CM001 allows the extra room through the back that a jacket requires.

One further test, rarely done and worth the trouble. Put the coat on, fasten it, and stand square to a mirror. The collar should sit flat against the back of the neck with no gap. A gap there means the coat is pitched wrong for your posture, and it is the single most common fault in off-the-rail outerwear. It cannot be adjusted cheaply, and it will show in every photograph taken from behind for ten years.

Sleeve length and the shirt cuff

Sleeve length is the detail most often left unexamined, and it is the cheapest to correct.

A coat sleeve should finish at the wrist bone, with roughly half a centimetre of shirt cuff showing beneath it. That small band of white is not decoration. It is the visual proof that the layers underneath were considered, and its absence is what makes an otherwise good coat look borrowed.

Too long and the hand disappears, which shortens the arm and ages the whole outfit. Too short and the coat looks outgrown. Both are correctable by any competent tailor for a fraction of the coat price, and both are worth correcting on the day of purchase rather than at some later point that never arrives.

Check the length with the arm hanging naturally, not held out for inspection. Then bend the elbow. A sleeve that rides up three centimetres when the arm bends is cut too narrow through the bicep, and no shortening will fix that.

Weight, and what it tells you

Pick the coat up off the rail. Weight is the most honest single piece of information a coat gives you, and it takes two seconds to gather.

A wool coat that feels light in the hand is usually light because the cloth is thin, the lining is minimal, or both. Thin cloth loses its shape at the elbow and seat within two seasons. It also loses heat, which is the one thing a winter coat is actually for.

A heavy coat is not automatically a good one. Weight from dense, tightly woven cloth is useful. Weight from heavy padding and bulky interfacing is not, because it stiffens the garment and makes it hang away from the body rather than with it.

Learn the difference by hand. Press the cloth between thumb and finger. Good coating recovers immediately and feels dense rather than fluffy. Rub it lightly. Fibres that lift and pill under a few seconds of friction will pill across the whole coat by February. The Coat 02 is made in a cloth with that density, which is why it keeps a clean line through a full winter rather than softening into shapelessness.

There is a seasonal trap in this. Coats bought in late autumn tend to be chosen for how they look in a warm shop. Coats bought at the end of a winter, when the body remembers being cold, tend to be chosen for how they work. The second instinct is the better one. If a coat is being bought in October, it is worth spending a moment recalling February before committing.

Lining and seams

Turn the coat inside out, or as far inside out as the rail allows. The inside is where cost is cut, because almost nobody looks.

A full lining is not a luxury. It is what lets a coat slide over a jacket instead of dragging on it, and it is what stops the outer cloth from being abraded by everything worn underneath. Half linings and bagged linings are acceptable in lighter weights. In a winter coat they are a compromise you will feel every time you put it on over knitwear.

Look at the seams. They should lie flat, with no puckering along the length and no gathering where two panels meet. Check the armhole seam in particular, since that is where stress concentrates. Check the pocket corners, which are the first place a coat fails. A small bar tack at each corner is the sign of a maker who expects the coat to be used.

Buttons and closures deserve the same attention. Horn and corozo are repairable and age well. Thin plastic cracks. The button shank should have a little length to it, so the button sits above the cloth rather than pulling into it when fastened.

These details are what separate a coat that gets better with wear from one that merely gets older, a distinction worth reading in full in on things that improve with age.

Length and your height

Length is the decision that ages fastest if it is made for a season rather than for a body.

The reliable points are three. Mid-thigh, which is the shortest length that still reads as a coat rather than a jacket. Just below the knee, which is the most versatile and the most forgiving over almost everything else. Mid-calf, which is the most formal and the least adaptable.

Height matters less than proportion. The test is where the hem cuts the leg. A hem that lands exactly at the knee cap divides the leg at its widest point and shortens it. Two centimetres above or five below is better. On a shorter frame, below the knee can work beautifully, provided the coat is narrow enough not to overwhelm.

Consider also what goes underneath. A coat intended to cover tailoring needs to finish below the jacket hem, or the jacket will show and the line will break. A coat worn mostly over knitwear and trousers has more freedom. The Coat 02 CM002 sits at the longer end of useful, and for those who want the warmth of an outer layer without the sleeve commitment, the Cape 02 solves the same problem from a different direction.

Colour belongs to this section rather than its own, because length and colour together decide how often a coat gets worn. Navy, charcoal, camel and black all work across a whole wardrobe. A strong colour is a pleasure for two winters and a constraint for the following eight, because it has to be reconciled with everything underneath it every morning. A restrained coat in a cloth with real depth to it will outlast an interesting one, and will be reached for more often, which is the only measure that matters by the sixth year.

The fitting-room checklist

Take this in with you. It takes four minutes and it is the difference between a coat that lasts and a coat that is quietly replaced.

Wear what you will actually wear underneath. A coat tried over a T-shirt and worn over a jumper is a different coat.

Check the shoulder seam against your own shoulder edge. Reach forward. Note any pulling across the back.

Fasten every closure and sit down. A coat that cannot be sat in while fastened will be worn open all winter, which defeats the purpose.

Raise both arms halfway. The hem should not lift dramatically.

Look at the sleeve against your wrist bone. Decide then whether it needs shortening and factor the cost in.

Turn the collar up and down. It should sit cleanly both ways, without a gap at the back of the neck.

Look at the back view, which is what most people see. Walk four steps away from the mirror and turn.

Then stop. A coat that passes all of that is a coat worth keeping for a decade, and the rest is a matter of restraint rather than inspection.