i agree. its the wrong frame of mind to have, when you have fun and focus and are positive, you take things in, you get over you're mistakes quicker because you are in a more positive frame of mind, and have an attitude of 'i want to nail that, rather than i just cant do it!!!!!!'
i know its not the same, but when i first was learning to drive, i used to get flustrated when i did anything wrong, and be negative, and the more i got upset and mad, the more id panic and make more mistakes and take nothing in.
now im learning again, and im positive, and i have fun, but i listen, and focus, and everything is so much more easier and fun and less stressful. his attitude is really bad, hes got virtual no self belief in himself at the moment and when you tell yourself you cant do something, often you cant.