Boing! You have another email. Boing! Boing! There are two more emails to deal with. Right as you get ready to leave for lunch Boing! Boing! Boing! Arghhh! This is not what email is for!
If you want to get more done, turn off the audio notification for email. You can turn it back on if you are waiting for an important message, but leave it off while you are trying to do normal work. The whole point of email is so you can communicate quickly but asynchronously. That means it is ok to wait a few minutes before typing a reply.
You can’t let every email be an interruption. Go ahead and check your email every 15 minutes if you must, but spend those 15 minutes in between getting some real work done–not jumping to serve the email gods every time your inbox makes a sound.