Re:Why not apply spam filters on outgoing messages (Score 1)

There's a big difference between filtering incoming spam and filtering outgoing spam. When spam comes in, it doesn't get blocked, it just gets put into your spam folder, which you should check periodically to make sure it hasn't collected any real mail by accident. There is not, however, any protocol by which an outbound server can place spam in your spam folder, they would have to block it outright. This means that certain, totally acceptable emails will be blocked, not a good thing. Moreover, most spam filters, including Google's, have a very important feature by which you can set particular senders as "not spam," this would also be impossible for an outbound server to allow you to do. Moral of the story, if you don't like having your mail randomly blocked, and you expect to ever get legitimate emails from someone using gmail, having gmail filter outgoing mail is a bad idea.