Life... is not simply a series of exciting new ventures. The future is not always a whole new ball game. There tends to be unfinished business. One trails all sorts of things around with one, things that simply won't be got rid of.
In real life, it is the hare who wins. Every time. Look around you. And in any case it is my contention that Aesop was writing for the tortoise market. Hares have no time to read. They are too busy winning the game.