Although I do understand why a VA won't initially pick up the phone to avoid getting caught off guard, I never really understood the concept behind not providing a phone number for a client or PC to call even though I've read all the reasons in that last thread as well.
Since the economic crisis, exceptional customer service and trust are the only things we have now in this world and people want to hear you over the phone, if they can't meet you in person. This gives them an idea of your personality, style, patience level, literacy, etc., in addition to getting a sense of whether or not they feel comfortable working with you and if the relationship would be a match. For these same reasons, I want the phone contact with PCs as well. Its makes for a great business model.
After all, we will have their company and private information at our fingertips and in a cyberspace, identity theft and character defamating world, its vital to make a PC feel at ease with you. I don't think it really has anything to do with bieng desperate for work, or anthing of that nature....but just plain old quality customer service that would put you above the others.
Just my 1.5 cents