If you are organising some form of business competition:
Try to get the location right.
Try to get the timetable right - busy people don't need to be surprised by something running an hour and a half longer than they anticipated.
Try to get the rules of the competition right.
Try to get the available facilities right - do the competitors need to supply their own PC or don't they?
If you are going to lock the competitors in a room for hours on end, at least warn them to bring some water.
Don't get me wrong, I appreciate the efforts of the people who gave their time, and I am sure that none of this was intentional, but I hope they get some of this stuff sorted for next year, for the sake of next year's entrants.