Every few years a brand decides its range has grown too long, and someone brings a slide saying that fewer choices sell more. Sometimes they do. The careful studies of real assortment cuts found gains, losses and something in between, and the differences tell you exactly where the risk sits.

The case for cutting

Boatwright and Nunes studied an online grocer that cut its range sharply. Across the 42 categories they examined, sales rose an average of 11%; sales rose in more than two-thirds of the categories, and 75% of households increased their overall spending Published. Customers “uniformly welcomed the elimination of clutter brought on by the reduction in redundant items,” but reacted in different ways to losing sizes, and category sales still depended on how many items were left Published.

An earlier set of experiments by Susan Broniarczyk, Wayne Hoyer and Leigh McAlister found that shoppers’ sense of how much choice a store offered barely changed when low-selling items were removed, as long as their favorite item was still there and the category kept its shelf space Published.

The case against

Sharad Borle, Boatwright, Nunes and two colleagues then went back to data from the same grocer. They say plainly that Boatwright and Nunes used a subset of the same categories and households Published. This time they compared 840 households who got the reduced range, where cuts ran from 24% to 91% of items in a category, with 378 who kept the full range. The cut lengthened the expected time between deliveries by 25.0% and lowered the expected order size by 4.8%, and it reduced overall store sales. Most of the loss came from customers shopping less often, not from smaller orders. Frequently bought categories were hurt less Published.

In between

Sloot, Fok and Verhoef studied a major Dutch retailer that removed a quarter of its detergents. They found “substantive short-term category sales losses but only a weak negative long-term category sales effect.” The losses came mainly from former buyers of the removed items. The smaller range also attracted new category buyers, and shoppers in the test stores searched faster Published.

PublishedFull references in Appendix C.

How to read them together

The studies aren’t contradicting each other so much as counting different things. Sales within the categories you cut can rise when clutter goes, while the customers who lost their item quietly shop less across the whole store. A category report shows the first. Only a customer-level comparison shows the second. The consistent threads:

• Cutting duplicates is mostly safe. Near-identical items that split the same buyers can go, and customers may find the range easier to shop.
• Cutting someone’s item is not. The losses concentrate in people whose product was removed, and they show up as fewer orders, not smaller ones. That’s a retention loss.
• Judge a cut by customers, not categories. Measure the ordering rate of affected customers against a comparison group, as Borle’s team did. A category sales chart will flatter you.

A cut can raise category sales and still lose customers. Only one of those shows up in the usual report.

Do this

• For your last range cut, pull the customers who had bought any removed product and compare their order frequency in the six months after with similar customers who hadn’t. If you’ve never cut, run the check before the next one, on the plan.