How can poor suppression hygiene trigger blocks?

Suppression hygiene failures:

What should be suppressed:

Hard bounces (invalid addresses)

Complaints (spam reports)

Unsubscribes

Role addresses (optional but recommended)

Failure consequences:

Continued sends to bounces (poor list quality signal)

Continued sends to complainers (more complaints)

Continued sends after unsubscribe (legal issues, complaints)

How blocks happen:

Accumulated negative signals

Patterns of bad sending behavior

Eventually triggers filtering or blocking

Prevention:

Real-time suppression processing

Regular suppression audits

Global suppression across all lists

Repeatedly shipping to addresses that rejected delivery triggers shipping bans.