You have probably seen the statistic. One cotton T-shirt takes around 2,700 litres of water to produce — about what a person drinks in two and a half years.

It is a real figure from real research, and it is used badly almost every time it appears. The number is not wrong. It is just doing less work than people think.

"Sustainable" is not a regulated word. Neither is "conscious", "responsible", "eco" or "mindfully made". Any brand can print any of them on any garment, and most do.

What cannot be faked is a specific answer to a specific question. Here are five worth asking — including of us.

You put the bag by the door with good intentions. Four shirts you have not worn in two years, off to the collection bin, and a small clean feeling on the walk home.

What happens after that is mostly invisible, and it is not what most people picture.

Clothes shed. Every wash pulls loose fibres off the surface of a garment and sends them down the drain — that part is unavoidable, and it has always happened.

What has changed is what the fibres are made of.

An 8-euro T-shirt feels like a bargain right up until you count how many times you actually wore it.

There is one number that tells you more about a garment than its price tag, and almost nobody runs it. Divide what you paid by the number of times you wore it. That is cost per wear, and it quietly reorders your entire wardrobe.

You have probably seen it on a product page and scrolled straight past it. 180 GSM. 220 GSM. Three letters and a number that tell you more about how a T-shirt will age than the price tag does.

GSM stands for grams per square metre — the weight of one square metre of the fabric. That is the whole definition. But that single number quietly decides whether your shirt drapes or clings, whether it survives a summer or a decade, and whether you can see your skin through it in daylight.