Every roll in the shop was paid for. Until it is cut and billed it is not stock in any useful sense — it is cash that has been converted into something you cannot spend, sitting where you cannot see it.
That is fine for the cloth that moves. The problem is the cloth that does not: the shade nobody asked for after the season it was fashionable, the bulk buy that seemed cheap at the time, the roll bought for a customer who never came back. It does not announce itself. It simply occupies the shelf, quietly, for years, and every shop has more of it than the owner would guess.
Then there are the cut pieces. The metre and a half left after a lehenga is genuinely useful — it is a blouse, a lining, a child’s garment — and it is almost never recorded anywhere, so it gets used at random or not at all. Shops that count their remnants find they are buying cloth they already own.
And shade lots matter more than the shade. Two rolls of the same colour from different lots will not match under a hall light, which is discovered at the fitting rather than at the cutting table. Recording the lot with the roll is a small habit that prevents an expensive remake.