If you think listing an item at anytime of day will make your listing equally as successful, think again. What may be convenient for you, say 4:00pm on a weekday when you're not in classes, or at work, may not be ideal for someone else. eBay's listings end on 24 hour intervals, no matter what time of day you start them on. So if you listed an item to begin at 4:00pm CST, that would be 2:00pm on the west coast (when generally people are not home on a given weekday). So if you want to discourage bidders say in California or British Columbia from bidding, I wouldn't suggest listing an item as this time.
Never use a 1-day listing unless you want to sell something that is time sensitive, such as concert tickets at the last minute for example. You also have to be an established member of the eBay community to even have the option to serve a 1-day listing. Generally, when do most people have the greatest amount of spare time? On the weekends. Choose to list your items based upon the schedule of society.