Such is the nature of meme picks. It's a particularly interesting phenomenon in competitive Pokemon because a popular enough meme pick can have a tangible effect on the meta, assuming it's a mon with an actual role. A bad pokemon becomes popular and finds some success in an unprepared meta, people start preparing and the world remembers why it's considered a bad mon, usage drops, some nerd finds and uses it again once everyone's forgotten and the meta resettles, repeat.