I made a Champions Team with NO STRATEGY... AND IT IS CONSISTANT WITH WINS!!!

Sure, but all you have to do is keep hitting until Protect fails! AOE attacks work for this, too.

It probably doesn't help that I've very rarely played against other Trainers; it's usually against battle gauntlets at the end of the games… 😒

This assumes that the second opposing Pokémon is doing nothing. They could be KOing your Pokémon, or setting up Trick Room or Tailwind to change the speed order, or any other number of activities. And they'd be doing it safely because you're hitting a Protect and making no progress.