There are also hiring ads run just to convince potential customers that you are not dieing. I know a few people who saw a job ad seeming to target them, with no response to their resume despite having a very unique skill set. Only by talking to insiders did the truth come out : they have enough people with the unique skill set but they need to appear to be growing even when it obviously is a dieing area. (mainframes in this case, they still exist and sell well but everybody has known they are on the way out)