OSA and OOS: availability of a product on the shelf and its absence

OSA helps merchandising managers see which agreed products shoppers can find on the shelf. In this article, OOS means shelf absence, not necessarily absence of stock throughout the store. Stock in the back room or in transit does not confirm shelf availability. A check describes one moment, not availability throughout the day.

For a complete check, OSA is the number of present SKUs divided by the number on the agreed list; OOS uses confirmed missing SKUs over the same list. Multiply by one hundred for percentages. Their sum is one hundred percent only with the same base and moment, and every item classified as present or absent. An empty list gives no defined percentage. An unchecked item or unreadable photograph is unknown, not OOS. Report coverage and unknown items separately for an incomplete check; a share among checked items is not a result for the whole assortment.

Before a visit, fix the list applicable to the outlet: the MML or assortment-matrix version, effective dates and areas to inspect. Match the exact SKU, including its variant and pack: a similar product does not establish availability of the required item. Count unique SKUs, not units or facings. Apply an agreed rule to secondary displays; do not retrospectively change the list to improve the score.

A visit provides direct observation, a photo records the visible shelf and sales provide a signal of possible absence. Zero sales alone do not prove OOS: demand may be weak or till data incomplete. Photos need legibility, coverage, outlet identity and capture time. An old image does not establish the current state; uploading or processing the same frame again does not create a new observation. Review uncertain items separately; automation depends on the configured scenario.

The overall score depends on which outlets, SKUs and moments were checked. Results from visited stores cannot automatically represent the whole network. For comparable observations, total present and checked items before calculating the share, and report list coverage separately. A simple average of store percentages can distort the result. Show rechecks after replenishment separately from the initial observations; otherwise corrected outlets receive more weight. The share of successful checks is not the share of time a product was available.

After confirming a shelf gap, establish whether stock is available in the back room, awaiting receipt, in transit or absent from the store. These situations need different actions and owners. OOS alone does not quantify lost revenue or prove an employee is at fault. Confirm a correction by checking the shelf again, not only by marking a task complete.