The internet has opened up a new world of possibilities for the benefit of everyone in our society, not least of which job seekers. In fact, job websites have really made it TOO EASY to apply for jobs. As a result, candidates can easily submit their resume to any job that sounds remotely interesting to them.
Have you heard the expression "if it's so easy why isn't EVERYONE doing it?" Well, applying for jobs online IS so easy that EVERYONE IS doing it! As a result of this you send your resume into the great internet abyss and you receive NO feedback at all! You don't know if the position has been filled, if you were under- or over-qualified, or if you were second in line for the position and just out of poor luck for you the company was able to hire their first choice.
Here's a great video that illustrates this point: