This is an estimate, not a promise. It's deliberately conservative for cold email to local trades: on its own, about 1 in 400 emails turns into a client, and each follow-up adds about 0.1% more. Each warm step adds odds: a positive reply about 3%, interested about 8% more, a demo sent about 10% more, a proposal about 20% more. So one lead that reaches a proposal is roughly a 1-in-3 chance. "Not interested" replies don't count as positive. The odds add up across all your leads, so they never quite hit 100% until a client actually says yes.