Job Interviews

Do you ever go into an interview with confidence and feeling positive through the whole thing? When you leave you feel that you are the right one for the job and you get that sense that the interview went great and you are sure you are going to get called for the job? That happened to me not too long ago. I felt confident that they would hire me and it has been 3 weeks and haven't heard a thing. It really is a let down and I do wish employers would take the time to call each person they interview to let them know either way if they got the job or not.