It doesn't matter because that's NOT the reason why spam is commonly not autodeleted. The reason is because of false positives. If you could be 100% certain of

It doesn't matter because that's NOT the reason why spam is commonly not autodeleted. The reason is because of false positives. If you could be 100% certain of never falsely flagging an email as spam, you would be totally OK with autodeleting them unless you're either just curious or specifically doing something with spam messages.