Why is the windshield wiper clear when moving upward but blurry when moving downward?

[MilesAnn]

The reason why the windshield wiper is clear when moving upward but blurry when moving downward is: the wiper blade becomes hardened and aged after prolonged use. It is recommended to replace it directly. If you don’t want to replace it temporarily, you can use fine sandpaper to polish the side of the wiper blade that contacts the glass. The wiper, also known as the windscreen wiper, is a device used to wipe away raindrops and dust attached to the vehicle's windshield, improving the driver's visibility and enhancing driving safety. Rear windows of vehicles such as hatchbacks and SUVs are also equipped with wipers. In addition to cars, other means of transportation, such as trains and trams, are also equipped with wipers. Some engineering machinery, such as cranes, are also equipped with wipers.