With technology advancements, many people are predicting email almost eliminating phone usage in the business world.  Companies are turning to email as a primary form of communication, believing it is effective.  However, email communication misses key ingredients that make it less effective than phone communication.
It is very difficult to convey emotion properly in written communication.  While this may seem more relevant to personal communication, it is actually very relevant to business communication.  Sincerity and urgency are two states of being that are hard to convey in a written context. Sincerity is especially important when communicating to someone you don’t know, because they have no idea of the type of person you are and therefore won’t trust you as much. In addition, you do not want to accidentally come across the wrong way, which can be easy to do when someone doesn’t know the types of things you normally say and how you actually mean them.  The intonation in your voice cues the listening person to how you mean what you are saying, and that is simply lost in written communication.
In addition to the potential miscommunication of emotion in email, email is also more easily ignored.  There is the spam folder, which your email may accidentally end up in.  And even if your email is delivered to the correct inbox, a person may not always respond.  Think of how many emails you have ignored.  Is this the primary way you want to reach out to your consumer base?  If you catch a person on the phone, they often feel obligated to hear you out, rather than press delete.
Email has it’s advantages, especially that you can mass produce a message rather than individually call someone to tell them the message.  However, if you find that you are having difficulty achieving your goal through email, pick up the phone and try.