Jacob Riis

When nothing seems to help, I go and look at a stonecutter hammering away at his rock perhaps a hundred times without so 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.

Source: https://www.reddit.com/r/oddlysatisfying/comments/mlisdi/the_way_this_rock_splits