Comparison

Auto vs manual campaigns: the role each plays in a clean account

Auto campaigns find keywords. Manual campaigns own keywords. Run both, in a specific relationship: auto for discovery, manual for control. Pretending you can skip auto is one of the biggest unforced errors.

 AutoManual Campaigns
TargetingAmazon picks keywords + products for youYou explicitly set keywords
Primary jobDiscover new high-converting search termsBid precisely on known converters
Typical ACoSHigher (15-40%)Lower (8-25%)
Spend share10-25% of total ad spend60-80% of total ad spend
Negation disciplineCritical - auto pulls junk tooImportant but lighter
Reporting cadenceWeekly harvest of new termsDaily/weekly for bid tuning

Use Auto when

Always run at least one auto campaign per SKU bucket. Even mature accounts benefit from auto discovery against new shopping behaviour.

Use Manual Campaigns when

Always. Manual is where 70%+ of spend lives in a mature account.

Operator's verdict

Run both. Auto's job is to find what works; manual's job is to scale what auto found. The harvest cadence (auto search terms -> negate junk -> graduate winners to manual) is the discipline that separates accounts that compound from accounts that plateau.