>>16361651Aki is extremely unlucky and even within a corporation, luck is a massive part of a vtuber's success.
Roboco was part of Cover's experimental period and just isn't very well produced as a result.
Mel and Choco both used to perform better before YouTube regulations cracked down on them. They couldn't keep up with the scene that rapidly changed and Mel in particular had the whole management issue that left her absent through the company's growth period.
Iofi just isn't very good at anything even though she does basically everything decently. She had an unfortunate start and early ID was expected to fail by most people so while she's okay she really needed to be something special to ever have had a chance.
Risu's probably the only one on the list who's actually at fault. She had a very strong start but she was a bit antagonistic to her viewership and slacked off a lot and lost her traction. At this point she's just kind of old hat.
I don't actually know shit about Anya.
Special mention on the topic of IDs is Moona who had a weak start, was expected to fail, had an assortment of controversy and issues when she began streaming and managed to pull it together by putting in the work. Iofi is unfortunate but Risu really has no excuse.