Category
Lead-gen playbooks are honest about the trade: an email address is borrowed attention, given in exchange for a promise. These boards design the promise carefully, keep it quickly, and prune what they capture, because a list that hates you is worse than a smaller one.
Run a giveaway where the prize does the targeting, every email is written before launch, non-winners convert within 48 hours, and the list is pruned before it ever touches your main audience.
Design a quiz where every question changes the recommendation, every result bucket gets its own flow, and the answers people volunteered actually shape what they receive.