Choosing cohort windows for beauty and home catalogs
Monthly cohorts hide replenishment cycles. Here is how we set windows that match how people actually repurchase.
A lipstick buyer and a mattress buyer do not return on the same rhythm. If you force both into a 30-day retention chart, the home catalog looks failed while beauty looks healthy—even when both businesses are sound.
We ask merchants for the median days between first and second order by top category. Beauty often sits between 35 and 70 days; larger home goods may stretch past 120. The cohort window should be long enough to catch a natural second purchase without waiting forever for noise to settle.
Once the window is set, label cohorts by acquisition month and by first-category. The dual cut shows whether a strong campaign month created loyal buyers or one-time bargain shoppers. That distinction matters more than a single blended retention percentage.
When stockouts interrupt a category, mark the gap on the chart. A missing SKU can flatten a cohort for reasons that have nothing to do with messaging. Sales performance readings should carry those annotations so leadership does not overcorrect the wrong lever.