Your check-out clerk inputs the wrong SKU or dollar amount.
Stock is shipped from the warehouse and misplaced because the numbers are hard to read.
Customers have a difficult time distinguishing varying shades of color, and perhaps reject an item because the color they saw in the store was not the same color they saw after returning home. Common sense alone tells us that light is an integral part of the retail environment. This is the root of lighting problems in many retail establishments - instead of looking at lighting as an ally, aiding us in getting our jobs done as well as significantly improving our bottomlines, too many retailers take it for granted. Lighting can work for us, rather than just with us, if we just earn how. As retailers, we run a store.