There's a trade-off with airflow that rarely gets talked about: flavor vs. coolness.

Open airflow cools the vapor and reduces harshness, but it also dilutes the flavor. If your customer is chasing the full taste of their CBD e-liquid, they might resist opening it up. That's fair. But in hot weather, a warm, tight hit can be genuinely unpleasant.

The trick is finding the sweet spot. Suggest they open the airflow just a little—enough to cool the vapor without losing all the flavor. It's a balancing act, but once they find it, they'll be set for the whole summer.