What’s the difference between “spam” and “promotions” filtering?

Spam filtering identifies unwanted, deceptive, or malicious messages. Spam-filtered mail is effectively rejected and hidden from users.

Promotions filtering categorizes legitimate commercial messages. These are wanted enough to deliver but classified as marketing content.

The intent differs fundamentally:

Spam filtering protects users from harm.

Tab filtering organizes wanted content by type.

Landing in Promotions means you passed legitimacy checks but were classified as commercial. Landing in spam means you failed trust evaluation.

Promotions is the merchant quarter. Spam is the impound lot.