Alan, I'm going to try one more approach. Every round I play has an expected value amount (EV). At the end of the
year, I have a total EV amount for all hands plays (cumulative EV). And by the end of the year, which represents "the long run" or long term, my actual results will be pretty close to accumulated EV. I have had one outlier year significantly below EV and one outlier year significantly above, but generally actual results are pretty close to accumulated EV.
So the goal is to play as many rounds as possible, accumulating as much EV as possible. Now in the process, actual results will go up and down like the stock market, but the overall trend (longterm) is upward. So quitting when having a "bad day", all that does is stifle the overall total EV. In other words....quitting early based on some artificial goal or target, cost me money.
It really boils down to long-term vs short-term thinking. YOU are thinking about short-term results. AP's are looking at long-term results. Quitting to preserve some sort of artificial short time goal, would be like a baseball team with a goal of being ahead after the second inning. That is NOT what matters. What matters is the score after 9 innings.