You're a farmer with an adequate piece of arable land. You start to grow a certain crop and the yield met your expectations, though not spectacular. This goes on for a couple of years, and suddenly you realise that the yields have actually been dwindling over the years; and that you've unknowingly lowered your expectations to align with the decreasing returns.
Would you spend more to purchase fertilisers to make the land fat, so that yields will increase once more? Or would you instead seek greener pastures that promise a fine harvest (short term or long term; you name it, you have it)? What would you do?
Probably the last thing to do is to sit and lower and lower and lower your expectations year by year. Ever seen a frog in a pot of gradually boiling water?