Has anyone ever taken a class with a famous/successful/well known actor that didn’t stand out?

Basically the title. Not saying they were necessarily bad, but more so just curious because you always see the romanticized stories of now famous actors that found success at some level or another being the most charismatic people in the world, “You knew the second she stood up from her desk she would be destined for the screen!!” Or something similar comes to mind, but I’ve always been curious if people have taken classes or schooling or worked with someone well known who just seemed decent at the time or who didn’t make huge waves overall, if that makes sense.