The believer is not satisfied with mediocrity; he doesn't want to just do the bare minimum, either for his faith or in his work. The believer aims highs, makes a firm resolve, strives hard, and excels in all efforts. The believer is not lazy, nor does he give up. We are told to try to be leaders in our fields, and to leave a lasting legacy and impact - both on a spiritual level, and at a civic level.
The Prophet (SAW) said: "Allah has prescribed excellence in all that you do"
Yasir Qadhi