Example Scenario
A promotion is run that offers a free Gift with Purchase:
The key is watching and understanding the numbers holistically to make informed decisions.
However, if the promotion drastically reduced your marketing cost per order beyond the higher fulfillment, it might still be a successful campaign!
This increase in cost is spread over the same revenue, meaning those costs are amortised less effectively. Your % Logistic Cost to AOV will worsen.
This means the order AOV does not increase, but you are fulfilling more items and weight (and thus incurring more 3PL and courier charges).