This is important to a day trader. I like to relate this to comedians. In comedy , I see that the comedians usually leave the stage when they have made a hit joke that cracked audience up real good and they just tell you there time is up and at this time the applause is higher the more. This leaves the comedian happy in his closest while the audience too enjoy the feel of their money.
In relation ton trading too , when you are at the top of your profit and you are not sure or certain of the next market spike or movement, instead you waiting for take profit you can exit the market and go with happiness with what you made already before price crash because most times when ovaction is laudest, some audience might start "criticizing and you get a wipe"