Your to-do list is probably full of routine tasks you already know how to do. An A+ problem is different: unfamiliar, high-impact, and worth several days of work. Solving it expands your productivity like enlarging a wheel, so each turn after yields far more output.
Let's imagine you have your to-do list. Most of the times these are B and C level problems because you know how to solve them. Yay! But this one is the A+ problem that you have no idea how to solve. We spend all day every day just crossing these things off and then we are happy at the end of the day, but then we're sad at the end of the month because we still haven't solved the one big problem. And so you have to be comfortable with the idea that you might not solve it for one day or 2 days or 3 days or 4 days, but if you do solve it on the 5th day, it takes your wheel from a wheel that's this big to a wheel that's this big. And from that point going forward, when you're rolling, you're getting that much more for every revolution.
