Windshield wipers don't return to rest position

We have a 2003 Saturn L300. Wipers work fine in regards to the coverage area, but when my wife turns them off, they "rest" in the middle of the windshield. When she turns them on, then continue down to the bottom of the windshield, then go to the across the windshield and wipe normally. So, again, long story short, they stop in the middle of the windshield. Any suggestions? Thanks in advance.