" The Cul-de-Sac and the Cliff Are the Curves That Lead to Failure If you find yourself facing either of these two curves, you need to quit. Not soon, but right now. The biggest obstacle to success in life, as far as I can tell, is our inability to quit these curves soon enough. "

― Seth Godin , The Dip: A Little Book That Teaches You When to Quit (and When to Stick)