Is it bad to wash a car too often?

Washing your car improperly can damage it. Washing it as often as you’d like won’t hurt your vehicle, even if you do it every week.

Can you give an example not washing a car properly?

Don’t use household cleaning agents like hand soap, dishwashing detergent, or glass cleaner on the paint. These aren’t formulated for use on a car’s paint and may strip off the protective wax.