your thinking of it too simple minded, its all the bodybuilding bs thats out there.
think about a 100m sprinter (who most people want to actually look like, not kai green), they train right, then they take test for 2 weeks and gain 10%, then keep training and don't lose a bit, nothing. then next time they can (around testing) they do the same, over the years you get stupid benefits.
the same is for bodybuilders, but people blow it up too much... the thing is, it takes years to grow proper mature muscle, a 8 week cycle won't do it, but that doesn't mean you need to stay "ON" for longer. that is the mistake people make.
Its about the training, its about the food, its about the rest and sleep... if taking drugs was the answer there would be alot more champions. everyone "thinks" they are the best, eating perfect, train like an animal... they don't!!! people are delusional!