This is a really good comment. The principle, "Exits are harder than entries," comes up in a lot of different places. Hindsight bias distorts the picture. Wha

This is a really good comment. The principle, "Exits are harder than entries," comes up in a lot of different places. Hindsight bias distorts the picture. What could be more obvious than that, say, the Twitter guys were right to keep making Twitter even when nobody else cared. But whenever we think that way, we're retroactively assuming the power to predict the future. Then we find ourselves in some real situation that matters and that superpower doesn't work and we're totally stumped. (Edit: actually almost all our vocabulary around "persistence" assumes hindsight. When something turns out to have worked, you displayed plucky perseverance. When it fails, you were a stubborn fool. In real time, these qualities are not so easy to tell apart! Maybe they're the same thing sometimes.) So what do you do? It's a hard, deep question. I agree with stevenj. Consult the heart.