The important nuances of conversation are lost in an email.
Emails cannot replace the tone of voice, the interruptions inherent in face to face dialogue, the pauses that allow us to say, "Wait, I don't understand," or ask "Do you really mean that?" or even "That's not what I intended at all."
Emails allow issues to drag on. Allow the issue to fester, hurt, humiliate.
Emails allow cowards to punch their opponents in the gut with words.
The email recipient can't defend himself--especially when it's sent to a group. Prejudices root, misperceptions grow.
Emotional emails should go into a holding tank where they can cool off before they burn.
Emails allow us to write an attack before thinking through the logic.
Emails give a false power.
Just communicate face to face.
Emails build bridges.
Emails allow communication when there is no other means.
Emails foster friendship.
Emails are an easy way "to catch" someone without interrupting their life.
Emails are efficient. If I remember a message I need to convey at 6:00 a.m., I can do it without waking the recipient.
Emails, like nuclear energy, cars, and airplanes, can be used as weapons. Choose wisely when you write and respond to those emails.