Dear Catalog CEOs:
Have your data expert run a query. Aggregate the first order, second order, third order etc. across the customer life-cycle. Then, within each row of your query, measure the percentage of orders that are attributed to email marketing.
You're likely to observe that as the customer climbs the order ladder, the customer orders more and more often from email marketing.
When we look at campaigns, we don't see the world this way. We see that best customers love catalogs, so we send more catalogs.
But as the customer becomes more loyal, we frequently see that email marketing and direct load in the online channel take over.
This is a good thing. The more we see email take over, the more the customer is looking for discounts/promotions, or is just a fan of email marketing. The more we see direct load via the online channel take over, the more the customer loves our brand.