dude, we are talking about the very specific case of the agreement between 2 parties.
But I make it simpler so you even understand: If you are prescribed pills by your doctor and the prescription says to take 1 a day but you swallow the whole fucking box of 200 and get sick, are you gonna hold your doctor liable? After all it was only printed on the prescription, the doctor should have also told you, right? LOL
Of course you can't hold him liable. But if the doctor prescribes these pills knowing that they won't work for you, he can be.