In the Drive in movies the boys experience with waxing the family car shows that

"The Drive-In Movies" a story by American novelist Gary Soto, in wich the narrator is also a character who shows a hard work spirit; waxing the car is one of those tasks, which turned out badly due the boys ran out of wax and continued polishing harder but with only soxes and the wrong kind of wax so the car paint started coming off; therefore in summary, the most suitable answer would be that:

"the boys didn't have the proper tools or know-how to wax a car".