What’s the difference between complaint feedback vs bounce feedback?

Complaint feedback tells you that recipients actively marked your messages as spam. The mail was delivered successfully, but the recipient explicitly rejected it. This directly damages sender reputation.

Bounce feedback tells you that delivery failed. The address might be invalid (hard bounce), the mailbox full (soft bounce), or the server unavailable. Bounces indicate list quality issues rather than recipient rejection.

Both types of feedback require action. Complainers should be suppressed permanently. Hard bounces should be removed immediately. Soft bounces should be monitored and removed if they persist.

Complaints are merchants rejecting your cargo after inspection. Bounces are delivery trucks returning because the address does not exist. Different problems requiring different solutions, but both need attention.