Iseri Shihan used to say that we should embrace our incompetence.  Most of us however are too ashamed to do any such thing.  When we are confronted with our incompetence, we become defensive, close-minded, and though often in the wrong, we can come to feel perfectly fine with playing the role of the wronged.  Iseri Shihan spoke often against such a habitual pattern because it went against the very core of the learning process itself.  For Sensei, it was the antithesis of Shoshin, the very opposite of the Beginner's Mind.  It may be hard to imagine how becoming “victim” thereby puts an end to the learning process.  However, we should understand, being too big and being too small are two sides of the same coin.  Both put an end to the capacity of pure potential through the habitual reaction of egocentricism.

In Taoism, from which the "do" ending of "Aikido" is taken, there is a philosophical lesson that goes something like this - Sensei's point was itself based upon this position: 

"A Master, who is holding an empty vase, asks his disciple, who himself is stuck on his own incompetence, "What is it that makes this vase that I am holding useful?"  The disciple is very perplexed.  The answer is obvious to him, "The fact that I can put something in it."  The Master continued, "But what let's you put something in it?"  The disciple, a little less sure, answered, "The container itself."  The Master said, "You are wrong.  It is the hole.  The emptiness itself makes this vase useful.  If I take away the hole, the emptiness, by filing it with something, this vase will become useless.  The emptiness is pure potential.  The vase is only a chance manifestation.  Pure potential is what makes things useful."

Our mistakes, our incompetence, are like the emptiness of a vase.  In the making of them, if we embrace them, if we welcome them, we reach a state of full potential.  Hence why Sensei used to say that we should embrace our incompetence, for therein lies all of our possibility for growth, for improvement, for maturity, etc.  For Sensei, incompetence (e.g. our mistakes, our failings, our lack of skill, etc.) was not the end of our training; it was the very beginning of our training.  It should be this way for us as well.  To improve, you must do more than merely risk being wrong.  To improve, you must be wrong.  To become competent, you must first be incompetent.