Actually there are people who cannot make head nor tails of a blueprint - hence have all kinds of troubles following instructions based upon one. My nephew is highly intellegent with zero mechanical ability. Sometimes it just isn't there. With that said no one that I know of builds anything without making mistakes. Saw it apart and put it back together again. The more you build the easier it becomes - with fewer mistakes. Nothing I've ever built has been perfect but they've all flown just fine. Just my two cents.
John