The telephone is the most useful tool that has ever been invented, but most businessmen under utilise it. Telephones beats whatever kind of SMS-es or emails that you send out in this mordern era.
Hearing a real life voice speaking to you increases your confidence of the person that you are speaking too. We can determine from their tone whether they are in a mood to talk or if they are friendly or otherwise.
Many a business deals are sealed over the phone. With the advancements and rapid globalization, meetings can be carried out with people and associates from all over the world via tele-conferencing.
For a small retailer like myself, the telephone is my lifeline, be it the most sophisticated cell phone or the traditional tone dialled phones. I get orders over the phone. I go after my debtors over the phone and when I am free, I socialize over the phone.