This is one of those things that was so ubiquitous in the 1980s, and so absent afterward, that I had completely forgotten it until I saw one recently. (I spotted Elaine wearing one in an early Seinfeld episode.)
This artifact of the 1980s got its start in the "luxe" fashion trend. It was all about Gordon Gecko, Wall Street, stiletto heels, big poofy hair, and designer labels like Chanel and Gucci. I think it might have originally started with a hair decoration for equestriennes going fox hunting and other such upper-class horsey pursuits.
I mean, velvet, obviously! Super fancy!
In order to pull off the black velvet hair bow, you had to have fairly long hair. It had to be long enough that it would hang below your shoulders even once it was put up in a ponytail. This ruled me out of the black velvet ponytail for the first part of the 80s, because I had my hair short, in a series of ill-conceived asymmetrical cuts.
But once I grew my hair out, look out world! At the same time I was bleaching it with repeated applications of Sun-In, on top of trying to wrestle it into blonde-hood with monthly hair dye sessions. (It never worked. The best I could get was a shade halfway between "honey" and "carrot." But that didn't stop me. I was optimistic.) The combination of light hair and the black velvet hair bow was, I imagined, stunning.
Although it was meant to look super fancy, it clearly wasn't. While the origin of the black velvet hair bow may have been an actual black velvet ribbon, the truth on the streets was something quite different. Most of the time, it was a pre-made bow that had been glued to a hair clip. Sometimes a Scrunchi.
I mean, who had time to tie a damn bow in their hair? Also, I tried it once, with some leftover velvet ribbon. It ended up crooked, and it kept falling out of my hair. I guess this was something where you had to be rich enough to have, like, staff to do it for you. Me, I had 10 minutes before I had to leave for school, and half a bottle of Sun-In.
Of all the 80s fashion items, this is one that I don't see re-appearing any time soon. Maybe because it was the purview of everyone's least favorite 80s template, the ostentatious, brand-conscious queen of conspicuous consumption.