Often times, I am left to wonder why casting picks the people they do. The instructions say to dress nice, and I have seen so many in sloppy shirts, shorts and dirty sneakers get moved on through the process; while many well dressed and even "pretty" people get tossed aside, even while they passed tests.
Jeopardy on screen attire has become much less formal in recent years (remember the pizza chef guy from NYC in a track suit), but then so has everywhere else. Watch early episodes of TPIR and people are dressed up, now so many just look like slobs.