We were spending everything on finding new customers while our first buyers quietly never came back. The cheapest fix was already in the box. We added one printed insert to every order: not a discount code, a short guide on getting the most from what they just bought, plus one genuinely useful tip most people miss. Repeat purchase rate doubled over the next quarter. The insert cost cents. It worked because the moment a package arrives is the most attention a customer will ever give you, and most brands waste it on a receipt. Treat the unboxing like the start of a relationship, not the end of a transaction, and retention pays for the acquisition you were overspending on.