[w0utert]

In my own experience there is a very strong feedback-loop effect attached to the idea of staying optimistic about progress and not getting put off by all the problems you can see in the future.

I've realized on many occasions that I was being put off spending time on projects because of all the stuff I could think of that would take even more time, all the difficult problems I could already see or was sure to find along the way. It's paralyzing. But the effect of crossing off items on the eternal to-do list, the sense of progress, is strong enough to keep me going.

Maybe that's what the author describes as 'optimism': not getting paralyzed by bears down the road, so you can keep the positive feedback from progress going?