> How is this a negative effect? The amount of stuff that users are buying should be pretty much the _only_ metric you care about. Items ordered is most helpfu

> How is this a negative effect? The amount of stuff that users are buying should be pretty much the _only_ metric you care about. Items ordered is most helpful for making decisions when in context. It's awfully difficult to gauge health or make decisions with in isolation. A superficial short-term return may not be as beneficial on other levels - strategically, operationally, vendor ecosystem... The article and other commenters have pointed at some, a few more more basic things worth knowing: - return visit behavior. If infinite scroll diminished visitors favoriting items, what's the relative conversion for visitors returning to a list of favorites vs not? (features like this, Amazon Wish List etc, usually perform pretty well). - avg order value. Visitors are buying the same number of things, but are they making the same $$ per order? Preserving avg order value but increasing item count also increases operations overhead (which could be worth it to encourage a broader vendor pool...) - Clicks to items helps Etsy identify interesting/trending items&sellers independent of sales (move your data knowledge upstream!). Also increases the data size on individual users to build a taste profile and surface more items of interest at an individual level