How can bots harm my email list and reputation?

Invalid addresses: bot-submitted fake addresses bounce when you send, increasing bounce rates that damage sender reputation and may trigger ESP enforcement.

Spam traps: some bot submissions are trap addresses. Sending to them triggers blocklisting and reputation damage disproportionate to the address count.

Unwitting subscribers: bots submit real addresses belonging to uninvolved people. When you send, recipients complain (they never subscribed), damaging reputation through complaints.