I think when you practice somthing you must believe in it like having faith almost like a religion . actions without belief makes each motion empty the same in having belief in ones self and abilities . Im never cocky or arrogant but I like to believe im strong determined and i have great power in my strikes . Confidence is so important in every part of life . I tell my students who are afraid to spar to believe in themselves and what I show them . Once they start understanding what their bodies can do the skies the limit and they become my best fighters . More then anything having a strong belief in what you do and yourself is the greatest weapon you can have mixed in with hard training your ability can become even greater . I dont care whether your karate , mma, kickboxing , taekwondo or boxing if you dont believe in yourself you cant grow . Because you have already set a mental limitation to your development . Never give up and always believe in yourself and your abilities and always stay humble when some one is teaching you .