[eru]

Yes. And some people may take steroids, so they get strong without needing much proper stimulus.

[yummyfajitas]

I don't think this is true. My understanding is that steroids speed up your recovery phase - you can work out 7 days/week (and make commensurate gains) instead of simply 3 days + 4 recovery days.

They certainly don't prevent you from destroying your back during a deadlift with poor form.

[eru]

What about the stuff that makes cows gets muscles while just standing in the stables?

[matwood]

You are correct. Steroids allow the user to work harder and more often.