No, this is intentional safety behavior. When there are no conversions in the period (no purchases, leads or messages, depending on the metric), cost per conversion is undefined, not zero. If the system treated it as zero, a condition like less than X would be true for everything that didn't convert, and the rule could pause or change ads by mistake. (Imagine ROAS less than 1 pausing a WhatsApp campaign, which never has a purchase value.) That's why, when the denominator is zero, the rule skips that item without acting. If you want to catch what spends without converting, build the condition another way: Spend greater than X together with Purchases less than 1, for example.