I like how you pointed out both sides. Certainly, many wonderful things have been gained by persevering, not giving up something, even though it looked like a lost cause at that time. However, it is equally true that many wonderful things have been lost (fortunes, health, relationships, etc.) because someone kept on pressing for something that turned out to be an actual lost cause. So how do we know when to push on and when to give up? That takes wisdom.