One day, you might decide that you want to end an auction early. Before you do, though, you should consider why you want to do it: cancelling auctions upsets buyers and upsets eBay, and there might be a better to way to get what you want.
I Want to Change my Listing.
If you just want to revise your listing, you dont always need to end it. For listings that have more than 12 hours left to run and havent received any bids, you can revise almost everything. You can remove the Buy it Now price or reserve price, change the duration of the listing, or add listing upgrades.
If the listing already has one or more bids, then you can still add upgrades, or add to the description. You add more pictures too, if you want to. Once the listing gets into its last 12 hours, however, what you can do becomes far more limited, even if it has no bids: you can only really add to the description.
Its a very bad idea, by the way, to cancel one listing and ask bidders to bid on another listing for the same item instead. The chances are theyll be annoyed with you, and wont bother.
The Item is No Longer for Sale.
Perhaps you sold the item to someone else, you...