Most of the time it’s hard to tell whether the “celebrity” in question actually uttered the words in the quotation attributed to them. . .but I don’t put it past Abe to have said something so concise, and so wise.
It doesn’t matter what it is you do – whether you work, you don’t work, you help others, you’re studying in school, or taking out the trash. . .you should ALWAYS do that thing to the best of your ability.
Taking it a step further, I also believe a person should do it to the best of his or her ability no matter whether others can see them doing it – because in the scheme of things, the Universe doesn’t really care if you have an audience beyond yourself, and it.