This quote helps to put things in perspective. A person’s life is not developed all at once, but is built slowly by a series of experiences. You could also say, “One step at a time” – but I think this helps to visualize the long path ahead for all of us.
One drop on its own may not seem like much, but many drops together wield vast power. On a more practical note, think of this saying when you look at your savings account.