Ma Perkins (1933-60), The Romance of Helen Trent (1933-60), and Just Plain Bill (1933-55) were radio soap operas broadcast on different networks and sponsored by different companies but these, along with nearly 40 other programs, were all produced by Frank and Anne Hummert. As employees of an ad agency, the Hummerts applied the tenets of "reason-why" advertising not just to the commercials but to the programs themselves: they used repetitiousness and simple language to explain a problem (such as dirty laundry) and a solution (soap) carried out by idealized characters who likewise seek solutions to their problems in serialized narratives that extended for years. Their programs were all produced in an "assembly-line" script writing factory. Their work for clients such as Procter & Gamble, manufacturer of Ivory Soap,  is the reason that such serial dramas became known as "soap operas."