A product shows no days of cover, or reads "no sales data"

Days of cover is how long your stock lasts at the current sales rate. When a product has not sold in the periods the app measures, the rate is zero, and dividing by zero has no meaningful answer, so the app reports no data rather than inventing a number. Two consequences follow, and both surprise people:

• It will never be flagged as low. A product with no sales rate cannot be below your low-stock threshold, because it has no cover figure to compare against. It shows as out of stock only when its available quantity actually reaches zero.
• It will never be suggested for reorder. With no sales rate there is no demand to cover, so the suggested quantity is zero. This is correct for genuinely dead stock and unhelpful for a product you know is about to sell, such as a seasonal line or a brand-new SKU. Order those manually.