Junk mail discussion

[harm_less]

Gmail has a great spam filter. Go onto the web server and Mark As Spam some samples.
It learns and you no longer even see them next time.

Problem with Gmail's filter, it often will mark legit mail as spam. 

Theres many legit businesses that have their mail go to Spam, even though they aren't, and most people wont even bother looking in the spam folders to check something hasn't been marked by mistake.

Absolutely the case for us. We have ongoing problems with our website derived emails going to customers' spam folders and then having to resort to resending/forwarding using my Gmail account. As a business this can be interpreted by the intended recipient that we haven't bothered to reply to them which is a bad look!

Many people are oblivious to their spam folder's contents and only discover it by chance. Our email tracking service occasionally advises us that and email sent weeks/months or longer ago has finally been opened which I assume is due to a spam folder eventually being accessed. Likewise with unsubscribe advices being received well after a (Mailchimp) newsletter was sent.