This is somewhat similar to the saying, "The greatest oak was once a small seed." It means anything big or anyone successful needs to begin with the simplest. Before someone could do great things, he must get through the smallest steps first to go even beyond the big ones. To achieve goals, one must make efforts and hardships. There would not be a million without one. Just as the rich men were once poor. Famous were nobody for once, and all that are great came from being little.