Shino, I'm not sure you understand. Let's say I'm playing against your "perfect, unbreakable lock" deck. I have two Vulpix' on my bench. During your turn, you can only knock out one of them. I use this time to evolve into Ninetails to send your Goth back to the bench for the Shelmet you somehow have on your bench (Accelgor+Mew+Goth+Dusk+Darkrai+Venasaur is a full field), the Accelgor you have out so Mew can copy it, or break the lock next turn by sending up Venasaur (you have to use your attachment to retreat Venasaur, so you don't have the attachment to Deck and Cover). I can then use a switch to attack and either knock out the Shelmet/Accelgor or just put damage on Venasaur. Either way, that is 2 turns of your lock broken, which can be more if I Devo Spray the Ninetails.