User blog comment:IamJakuhoRaikoben/Chapter 361: The Two Bombs, Review./@comment-24066070-20131122224003/@comment-24066070-20131123101116

He likely didn't use the bomb spheres against FT, cuz he underestimated them. The whole thing where he left Lucy the choice was again underestimating the opponent, since he could've blown up Lucy and everyone else who was at that place.

People before me already pointed out that villains in pretty much any serie always leave the good guys a chance to turn the situation around. If they would always do "the most logical thing to do", namely just killing the good guys then not a single serie would have a happy ending.