It is very easy for us to focus on our past mistakes with an eye to preventing them in the future. This can be very counterproductive to attempting new things through worrying about repeating our mistakes.
Life is a never ending series of experiments. We cannot guarantee the future we believe will happen because we cannot control everything necessary for making it come true. Therefore we experiment using what we hope will happen.
In this light we should stop calling things that do not turn out the way we predicted mistakes. instead we should consider that everything up to now has been training. We are allowed to have imperfect results in training and so it mirrors life.