What does "unhealthy" mean in competitive battling?

As I write this question, people who know more than I do about Pokemon battling are suspecting Sablenite in OU. This is probably the first suspect test in my competitive battling career that affects me personally, as Sableye is on my OU team. Because of that, I’ve been reading more carefully about suspect testing. People were saying things like, “I’m not saying that mega Sableye is uncounterable, just that it’s unhealthy for the metagame.” From what I could understand, “unhealthy” means something like people having to put moves on their Pokemon just to counter mega Sableye or battles being decided before they start because one team has mega Sableye and the other team can’t counter it. How close to the truth am I?

Pleaselog inorregisterto add a comment.

From what I could understand, “unhealthy” means something like people having to put moves on their Pokemon just to counter mega Sableye or battles being decided before they start because one team has mega Sableye and the other team can’t counter it. How close to the truth am I?

That’s the gist of it. Due to its relative strength, the mere existence of a thing requires you to take steps to counter it before you even know if you’re going to face it, because it isso powerfulthat not having an answer to it before hand is basically suicide. This then begins to become a problem with strategic diversity, because having “mandatory” options narrows the field of possibility. You have to give up or reassign, in this case, moves in some Pokemon’s movesets, and potentially even entire Pokemon on your team, in order to have a counter available to deal with Mega Sableye.

This can, depending on the meta as a whole, become a feedback loop. Because you have fewer “free” slots, you now have to alter the makeup of your team in order to deal with this other threat that was manageable before, but is now a balancing act due to your reduced options. Which limits your flexibility for this third threat, and so on. If not dealt with, it can lead to your entire team being dictated based on a handful of individual things that are so powerful the meta as a whole revolves around their existence, and the methods of dealing with them.