Glossary
Bounce rate
The share of sends that come back undeliverable.
Hard bounces mean the address doesn't exist; soft bounces mean temporary failure (full inbox, server down). Mailbox providers read sustained hard-bounce rates above roughly 2% as evidence of a bought or rotting list.
Because bounces only show up after you send, they're a lagging indicator — validation turns them into a leading one.
In ListFunnel
ListFunnel's goal is that your send tool never meets the addresses that would have bounced.
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