Dining chairs soil in a very specific pattern, and once you know it you cannot unsee it. The front edge of the seat is where everything lands — it is directly under the plate, it is what people slide across when they sit down, and on a pale fabric it darkens into a visible band while the back half of the same pad still looks new. The seat itself takes food, drink and body oil through clothing. And the backs take hand contact, because that is what people grab to pull a chair out. So a set of six can look perfectly acceptable pushed under a table and thoroughly tired the moment they are pulled out for guests, which is exactly the wrong time to discover it.
They are also the pieces least likely ever to have been cleaned. A sofa gets a professional visit every few years in most households; dining chairs frequently go the entire life of the set without one. That matters more than it sounds, because food soil is not like the dust and body oil on a lounge — it is protein and it is oil, and both feed the sort of thing you would rather not have at the table. The grease element in particular does not respond to water-based cleaning at all, which is why sponging a dining chair at home so reliably fails and then leaves a ring around the area that was sponged.
The constraint that shapes the whole job is timber. Almost every dining chair has exposed wood — legs at minimum, often a full show-wood frame around the seat pad, sometimes a timber back with a small upholstered panel set into it. Water on that timber lifts the finish and leaves a white bloom that does not come out, so the work has to be tightly controlled: the pad is cleaned to its seam, the moisture is kept low, the wood is protected and dried immediately, and nothing is over-wet. It is finicky work rather than difficult work, and it is the reason a careful set of six takes an hour rather than fifteen minutes. Book it and the whole set comes back matching, with the timber untouched.
