Aracha is a trade good, not a product
The clearest case is Japanese green tea, where the manufacture is split between two businesses and the split is invisible on the packet. A grower's factory produces aracha: correctly steamed, rolled and dried, and containing long unbroken leaf, stem, buds and fines all together, at a moisture content too high to keep. A refiner buys it and runs an operation that has no Chinese equivalent — cutting the long leaf to a uniform length, screening it, winnowing it, and pulling the stem out with an electrostatic separator. What comes off that line is four teas rather than one tea with waste removed: sencha, kukicha, mecha and konacha. A drinker buying a shop's own sencha is buying the refining and the firing at least as much as the growing.
The final firing is a style decision, not a technicality
The refiner's last heat, hiire, takes the tea to storage moisture, and because it is applied to a tea that is already sorted its temperature is a choice rather than a requirement. Fire low and the marine, vegetal, fresh character the leaf came in with survives, and the tea is more delicate in both senses — it is also more perishable. Fire high and a nutty, roasted-grain sweetness develops that a Japanese buyer recognises immediately, and which several long-established houses have built their reputation on. Regional taste differs on it. Push the same lever much further and you stop producing sencha at all and produce hojicha, which is why the two operations share vocabulary and machinery and why a very strongly fired sencha genuinely sits between them. One machine, one setting, and most of the visible range of a category.
Sorting is a separation, not a hierarchy
Everything that comes out of a drier is a mixture, and sorting splits it by size, density, colour and magnetic response. The names that result — whole leaf, broken, fannings, dust in the orthodox vocabulary; BP, PF, PD and Dust in CTC — describe particle size, and particle size describes extraction speed. They say nothing about the garden, the season or the skill of the manufacture, and a factory can produce an excellent whole-leaf grade and a poor one on the same day from the same batch. The same point applies with more force to the Japanese fractions: konacha is not the dust left over from sencha, it is the fine fraction of the identical leaf, which is why the cup at a sushi counter is strong rather than poor. Reading a grade letter as a quality tier is the single commonest misreading in the tea trade.
Blending is the last operation of manufacture
Almost every tea sold under a repeatable name is blended, and the blending is a manufacturing step rather than something done to a finished tea. A taster works against a retained reference sample and builds a batch from what is available — a proportion for body, one for briskness, one for colour, one for aroma — to reproduce a fixed profile from inputs that change weekly. That is what a breakfast blend is; it is equally what a Japanese shop's own sencha is and what most jasmine is. The skill is the opposite of the skill in single-lot selling: not finding the best lot, but finding the combination that matches a target. Where it fails it fails visibly, and a familiar tea that has quietly changed character is usually a standard that could not be met from the season's leaf.
Resting, and the teas that are not finished when they are sold
The final and least visible tail belongs to roasted oolong. The tea is roasted, sealed and put away for weeks or months while the fire note recedes, tasted, and roasted again — two or three rounds, each separated by a rest. A tea sold too soon after its last roast is not the tea the producer intended, and the same tea a few months later is noticeably different without anyone having touched it. Buyers experience this as storage improving a tea, and producers experience it as a scheduling constraint that makes a heavily roasted oolong a product with a production cycle measured in seasons. It is the clearest case in tea of an operation whose most important component is an interval.