When I first read this book I was working at a company building a product that no one used. The company was propped up by investors and eventually folded. It's not a great feeling developing something that no one will miss when it disappears.
On the one hand, this is quite a normal and even healthy thing in nature, and apparently a part of life itself. A plant drops thousands of seeds, but only a few of them will ever sprout. We humans, too, will try many different things, and only a few of those will turn out worthwhile. It is a process necessary to adapt to an ever-changing environment.
On the other hand, we could probably do a better job of recognizing and admitting blind alleys sooner. In groups, especially, it is very easy that people will convince each other that the path they are on is viable. But I can assure you, even if you worked for yourself, you would still fool yourself often enough. Not only would you still tend to continue working on things that I have already proven to be failures. But you would actively avoid asking the question, βIs this thing I am working on still worthwhile?β. I think once we are in execution mode, switching back to the higher plane of strategy and critical distance is a very hard and counter-intuitive thing to do.