While putting 100% effort toward a worthy goal is ideal, if such effort is not built upon your own progression in knowledge and self-improvement then it can lead to eventual stalling and failure. Often people start out giving 100%, but because they are not improving as a person they cannot maintain and come back to average or even worse than when they started!
Lack Of Self-Improvement Can Lead To A Regression To The Mean Or Worse!
These are actually enormous ideas.