IMHO a bochur who doesn’t grow a beard should shave either every day or every 2 days (depending how fast/slow the hairs come in. No matter where you are, you must look like a mentch and not with this new mishigas ‘stubble look’ which became quite fashionable and commom today. I think it’s messy, lazy looking, and has hints of the ‘homeless-man’ look. pathetic. A girl is expected to wear makeup and dress ‘put together’, especially when in the parsha, a bochur is expected to do his hishtadlus and shave. Same goes for excercising daily, watching your weight, and getting enough sleep, to name a few.
Not shaving at that stage of life (shidduchim) shows he doesn’t care enough to make a nice impression, is lazy, and is a definite negative in my books.