Re: who's fault is it
Any of your boxers that have decided to fight and have prepared themselves for a bout should be commended. I've seen many a person down the gym pull out of fights for bullshit reasons or simply not have the bottle to enter the ring.
If I fighter doesn't prepare properly or doesn't take a fight seriously, then yes you can be angry.
If someone turns up on fight night after working hard, but perhaps nerves, fear or just the whole occasion gets them and they perform poorly they deserve your guidance and support, not your ridicule.