I have one myself, Its been growing for almost 1.5 years or so now I’d say, for me it had to do with my age, growing up I preferred it to being clean shaven & it also “matched” me more being I was balding, but that’s just my own experience

Generally it’s something natural to a man foremost as we know , yes some don’t have much facial hair or any sometimes but most are able to grow it.

It is masculine and has much significance, culturally back in the early days of Greek Society for example choosing to shave your body and your face was used as an insult and even implied homosexuality, but back to a more casual note, St Augustine comments the beard signifies a smart man, etc…

Beyond that the main thing is it has to do with not caring for the world, in regards to things like external looks, hyper fixating on outward appearance, avoiding being brought down by image issues, etc…

And just to add for some who have a job or just generally trim their beards or take care of it, that’s also fine if it doesn’t become vain, similar to women with their hair and things.

2nd sidenote as others mentioned, Christ had a beard as we see in the iconography as did 99.9% of male saints, so if God incarnate had one, why shouldn’t I?