The expression
in math means that function f(x) can be made to be as close to L by making x sufficiently close to c. In other words, if f(x) wanted to become like L then it must extend its x limits to be like c which belongs to L.
Someone said that there is no limit to what a man can do or where he can go, if he doesn't mind who gets the credit.
However, even though I don't mind at all who's getting the credit, I seems to be lacking in getting my xs even near to the required cs, as if they are always out of my limit in all my participation so far, notwithstanding my life and work experience. It's a kind of mystery, of which I'm not feeling awe at all.
As the narrator in The Outer Limits tv series said, "...you are about to participate in a great adventure. You are about to experience the awe and mystery which reaches from the inner mind ..."