Retail packaging is a strange animal. There are many factors that determine how many pieces are sold in a retail pack These include things like shelf size available, competition, price points, marketing, and tradition.
Here are some details retailers use:
- Shelf size- Retail shelf space is very valuable. Retailers measure shelf value in sales per inch. Grocery stores and mass merchandisers use pretty standard metal gondola shelves with height adjustable shelves. They normally come in 48 inch lengths and vary in depth from 12 inches to about 36 inches deep. Some are more, some are less depending on the retailer or product type. Retail merchandise must fit on those shelves.Manufacturers ship merchandise to retailers in what they call standard packs. 2 piece, 6 piece, 10 piece, etc whatever fits into a convenient size shipping carton. Retailers order merchandise in multiples of these standard packs.When retailers order merchandise they try to make sure everything fits on the retail shelf. They don’t want to keep merchandise in their back room or warehouse.
- Competition- In products like diapers, manufacturers pack quantity to meet or exceed their competition while still maintaining a competitive price point and preserving profit margin. The standard pieced pack must also fit on the shelf. Remember, for many retail items the packaging may cost as much as the contents of the package. Examples are perfumes in fancy bottles, liquor in fancy bottles, product packed in theft resistant clam shell packaging. Adding one more piece to a package may not cost anything additional.
- Price points- Retailers used to like to maintain what they call charm pricing, $9.99, $12.99, $19.99, $24.95, etc. Now this has been changed a little by retailers like Wal-mart that have change pricing strategy to non standard price points, but it is still factored into piece count quantity.. If a competitor sells 16 pieces for $19.99, a different manufacturer may try and sell 17 pieces for $19.99 to offer a better value and hopefully still be profitable. It’s all about perceived marketing value and profit margin.
- Marketing- Manufacturers want to sell product and maintain and grow market share. They use quantity to attract customers. Think about how many products you see with new improved packaging, 2o% more product for the same price, bonus sample bottles with the purchase of a full size bottle and so forth. It also works the opposite way. Look at canned vegetables. The cans used to be 16 ounces, now most are 15 ounces but sell for the same price as the 16 ounce can. Marketers hope the customers don’t notice the smaller sized can, and bank on this being more effective in preserving profit margin, than raising prices on the 16 ounce can.
- Tradition also plays a role in packaging, 6 packs for beer or soda, 100 pieces per bottle for aspirin, a dozen donuts, and so on.
To summarize and answer your question, packaging is all about shelf size, competition, marketing, tradition, and profits.