Customer Purchase Latency is a measurement of the delay between customer purchase events (orders). It's in the form of a time, usually a number of days. So a 30 day Customer Purchase Latency means 30 days pass between orders.
This is usually aggregated across all of your customers into Average Customer Purchase Latency.
Eric Davis
How do your products determine customer behavior
In Repeat Customer Insights the Customer First Product analysis will measure customer behavior based on the products each customer first ordered.