There's lot available on the internet to learn about competitive pokemon. Something like this (https://www.youtube.com/watch?v=yBw6UXAiq0A) is a good entrypoint. But even better - go to a competition with your kids! If they're interested, of course.
A very weak Pokemon, but had the right moves and right team support.
The video game is far more about teamwork and team composition than just throwing the highest stat Pokemon at each other.
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Stats matter for your sweeper (attack and speed), pivot (attack and defense) and sponge (hp and defense).
But there are a whole slew of 'trickster' Pokemon, like Pachirisu, Ninjask, klefki, whimsicott and others who have rare moves and/or abilities that can beat raw stats in the right situation.
Some lower stat Pokemon, like Clefable, are used despite better stat Pokemon (ex Blissy for sponge purposes) because of teamwork, movesets, typing, or abilities.
Unless you talk about pokemon TCG, and in this case, 8 don't know.