It is the input every stock decision multiplies, and the one demand planning cannot do without. Cover, reorder points and safety stock all scale with it, so an extra fortnight of lead time raises the stock a store must hold and the cash tied up in it, which is a real cost of choosing a cheaper distant supplier. nouz keeps it per product rather than per variant, since the variants of one product usually come from one supplier, with one default for the whole store; setting lead times in nouz is done on the Products page.
Measure it door to shelf. A supplier who ships in thirty days into a port that takes ten and a warehouse that takes three has a 43-day lead time, and the three days at the end are the ones everybody forgets and the ones most easily fixed.
Its variability matters as much as its length. A reliable 45 days needs far less safety cover than an unpredictable range of 30 to 60, and the honest way to size that cushion is from how late the last several orders actually were, which a safety stock calculator turns into units and days of cover.
