The model calculates expected value based on five parameters, and a merchant can override each of them:

Retry cost — processor and gateway fee per retry attempt. $0.12 by default
Margin rate — gross margin used to compute expected value. Default resolves from merchant_vertical: SaaS 75%, digital goods 70%, high-risk 40%, e-commerce 30%, marketplace 15%, travel 10%; 35% fallback if vertical is omitted
Friction cost — cardholder-annoyance cost per retry. $0.03 by default
Recovery threshold — retry only if the model's recovery probability is above this. 10% by default
Minimum retry expected value — retry only if expected value clears this floor. $1.00 by default — prevents tiny-amount waste where retry cost plus friction eats the recovery