The Society believes that as preachers salesman they are representing Jehovah the WTBTS by preaching selling literature about his coming kingdom.
Jehovah's Witnesses are known for being in the publics eye. Having men in suits and woman in dresses makes it appear that they are honest people. They appear to represent Jehovah the WTBTS as best as they can. So, they appear clean cut and well kept when being out in public. A beard would not represent the WTBTS. It would show '' brazen conduct ''.
In the 35 years as a Witness, I never saw a beard in my congregation. Sideburns were to be trimmed after a certain length, hair that was hanging on your shirt collar was to be trimmed. If you would not abide by these rules you couldn't give a talk. Colored shits and wild ties were frowned upon.
It's a stupid rule by stupid old men in New York. True preachers saleman is what they are.