If you are using Gmail and you are not checking the spam folder at least once a week there is a good chance you are missing legit emails.
At least, this has been my experience for a while now.
edit: typo
At least, this has been my experience for a while now.
edit: typo
I've kept those "tags" turned off on every Gmail account I control — I'd rather not risk having something important enter "social" or "promotions".
https://webapps.stackexchange.com/questions/69442/how-to-dis...
edit: and even then they think they know better and trash some mails as regardless.