
A coat of wax might hold a few weeks in a mild climate. Under the Las Vegas sun it breaks down fast. That is the gap ceramic coating fills.
Ceramic coating bonds to the paint and adds a hard, slick layer. Water and dirt have a harder time sticking, so the car stays cleaner and washes off easier. The gloss holds far longer than wax.
Ceramic and paint protection film are not either-or. Many owners run PPF on the high-impact panels and ceramic over the rest, so the whole car is easier to keep and better protected against the sun.