You know what really annoys me about job applications?
I mean other than all the hoops you have to jump through, all the forms with their crazy complicated questions, and spending all day travelling to an interview which ultimately turns out to be a complete waste of time.
What I really hate is when companies don't bother to let you know you've been unsuccessful.
I just don't understand it. Surely it only takes a second these days to shoot off an email informing you of your unsuitability? You can easily mass-send the thing to everyone. I only see this as being polite. If I've gone to all the effort of applying to you, the least you can do is send a note saying 'sorry, but we've employed someone else.'
This is a thousand times worse when you've been to an interview. I went to an interview over four years ago and have yet to be told I didn't get the job. Sounds crazy, doesn't it? I know I didn't get the job because the interview went horribly. I was definitely not suitable for the position and this was apparent within a few minutes of the interview starting. To be honest, I was shocked when I managed to get as far through the process as an interview - I can only put it down to living locally and thus they figured they might as well see on the off-chance.
Informing people takes no money and very little time. The only thing that comes from not informing people is a bad impression of the company.