When an interviewer becomes invisible, it is often an indicator that he or she would like you to disappear too. If this is the company's way of telling you that you are not being offered a job, it is unprofessional, disrespectful, and unkind. It is also telling you something about the company's style of doing business, particularly in terms of the way it treats people.
At the same time, there could be some understandable reasons for the lack of follow-though with you. In today's topsy-turvy economy, perhaps the individual who interviewed you is now knee-deep in emergences that are consuming virtually all of his time. This does not excuse his failure to contact you, but it may explain it. In fact, there could be any number of urgent matters that are preventing him from getting back to you on a timely basis.
If you really want this job, you have nothing to lose by continuing to make intermittent phone calls, particularly early in the morning or in the early evening, along with some e-mail. Any message that you leave should emphasize the value that you bring to the company and the importance of responding to you as soon as possible. In the meantime, since this company is making no effort to pursue you, you should be making an effort to pursue other companies.
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