"When nothing seems to help, I go and look at a stonecutter hammering away at his rock perhaps a hundred times without as much as a crack showing in it. Yet at the hundred and first blow it will split in two, and I know it was not that blow that did it, but all that had gone before." – Jacob Riis
It's hard to know to what degree what you're doing right now is contributing to what you'll be doing in the future.
This visual is easily the most resonant I have created — I think because it reflects a truth that many of us have either experienced, or are hoping is the case when we're toiling away without a payoff in sight.