My wipers lately park in the extreme “up” (all the way left) position. The only way to get them to park in the normal “down” position is to use an intermittent wiper setting, wait for the pause between strokes, and then turn it off. It’s a 2002 model.
You might need a new wiper motor.
The wiper motor has a park switch for the wipers. This means when you cut the power off to the wipers, it draws a cam in that holds the contacts closed to the wiper motor so they operate to the point where the cam comes around, opens the contacts and the wipers park.