I rowed crew in high school with two guys who made it to the Olympics and won medals. I quit before college! In retrospect (after reading "The Dip"), this WAS the right decision, and I quit for the right reason: I'm 5'10" -- my legs are simply too short too compete on a world class level.
When I slogged through the dip: I've wanted to write a book for a long time, and have even had publishers interested (in the wrong topics and titles for me). I persevered, and eventually co-authored "Blogging for Business" with a friend and then "What No One Ever Tells You About Blogging and Podcasting." MANY people told me to "give up" -- no "real" publisher would accept a biz book proposal from me, a "technical guy." Books are selling well (by my standards, not Seth's!), and business is booming. Next dip ahead? Well, take it to the next level. Maybe not Seth's level yet, but to where I can impact and help more people, and of course help myself and my family more as well.
Publishing is no big deal these days with blogs and ebooks and Seth's Squidoo. I even coined a new term "squidbook" and have published two books so far. The hard part is to sell it and make a profit. Knowing when to quit is a good skill to acquire. It frees up your resources and energy and redirect them to something new and perhaps more rewarding. For me, it is about setting priorities. The term "dip" is a brilliant description. It captures the essense of re-direction.
"Dip" is a brilliant term. It also implies a feeling that the effort exerted is being wasted, and for most people it is, as they won't make it through the dip. I'm doing OK at selling my books, but the distance between "OK" and my definition of success has a wide, deep, dip.
Sometimes not making it through the dip can be OK. Is it a winner take all scenario, or are there at least some rewards along the way, and is the journey enjoyable?