User blog comment:IamJakuhoRaikoben/Chapter 418: Challenger, Review./@comment-76.108.4.129-20150203145229/@comment-5894890-20150204001242

Well for me, Lucy is one of my favourite characters, thus I want her to be stronger, display new attacks, and show me how much more awesome she has become. While it's true, Mashima hasn't shown any reason for her to get stronger yet, in past she did want to get stronger for her guild. (Erza: "As long as a have enough power to protective the ones I care about, I don't care how weak I am" <--- something along those lines. I think this would be a reason for Lucy as well, and also not wanting to rely on others). It's already been slightly hinted that she did get stronger by being able to predict the strength of those mages, she displayed a rather casual demeanour in determining it too, as if it isn't a big deal.