We had a guy who could unload a truck faster than 2 guys could sort it. He worked another full-time job while waiting for a driving position to open up at UPS. He routinely brought his lunchbox into the trailers with him and ate while we caught up.
I did similar things when hiring. If the application wasn't complete, they'd have to have extended work history listed, such as a minimum of 2 years at their last job. Also, if I was asked for a pen after handing out an application, I'd inform them that they'd do better to take it home and fill it out, since it appeared that they weren't prepared to submit an application. If told that they wanted to fill it out right now or didn't have time, I'd tell them I didn't have a pen. I never had anyone NOT grasp what I was telling them by that time, even though I'd often have a pen right in my shirt pocket.
Appearances DO often give an impression that won't get them a second chance, but I've had people turn out to be the best employees I hired even though they didn't appear to be someone I should give a second thought.
I do get your point, I just wanted to point out that there is a possibility for outward appearances of something out of their control to be misleading. Allow them to give you a more detailed example of their desire to unimpress you
