Because it’s sometimes hard to discern from Backscatter (malicious bounce messages). See: https://en.m.wikipedia.org/wiki/Backscatter_(email) https://en.m.wiki

Because it’s sometimes hard to discern from Backscatter (malicious bounce messages). See: https://en.m.wikipedia.org/wiki/Backscatter_(email) https://en.m.wikipedia.org/wiki/Backscatter_(email)