Avoid promoting products that mostly create one-time customers.
Each product you promote has the potential to create multiple orders per customer. Some products are weak and don't lead to many repeat orders, while other products get customers hooked.
Avoid promoting these dead-end products in important places (e.g. homepage, email, ad campaigns). Save them for upsells, cross-sells, or as filler.
Otherwise your wasting much of your acquisition budget on one-off customers.
Eric Davis
Market to your customer's timing
Figure out how long customers wait in-between purchases and you have a key component for your marketing timing. This is the basis of the Average Latency metric and Order Sequence Report in Repeat Customer Insights.