Can one bad campaign tank reputation for future sends?

Yes, a single bad campaign can significantly damage reputation and affect deliverability for subsequent sends. The severity depends on how established your sending history is.

New senders or those with thin track records are especially vulnerable. One campaign that generates high complaints or spamtrap hits can crater reputation before any positive baseline is established.

Established senders with years of positive history have more buffer. A bad campaign hurts, but historical trust provides protection. Recovery is faster because providers have context suggesting the incident was an anomaly.

A bad campaign is like a captain who has one disastrous voyage. A veteran with decades of clean records gets investigated but keeps sailing. A new captain with one bad trip may lose their license entirely.