When is the last time you checked your spam folder?
You should every day! You should every time you open your email.
You may say...."Why...It's full of spam!"
True, most of the emails will be spam, but you may find an email from a recuiter or hiring manager that landed in your spam folder. It could be an email from someone you know (or want to get to know) from a networking or professional group you gave your business card to.
Don't let your mail program make the decision. YOU need to check. Open the spam folder and look. If you think it may not be spam, open it and check. If the email is not spam, take the time and be sure to mark it as "not spam".
Mail that you send out, may come back in your spam folder. Mail from people in your address book may land in your spam folder.
I know of a person who never checked their spam or junk mail folder and they had a job offer sitting in the spam email folder, it had been there a couple of weeks before they checked. Guess what...he did not get the job. He called, but they said they did not hear back and offered the job to someone else.
Get into a good habit of checking your spam or junk mail folder. I recommend you do it when you open your email program each time...you will be glad you did!