"Are you quitting because it is too difficult? Are you quitting because you don’t see the progress? Perhaps because it makes you feel incompetent?  None of the reasons above are good indicators to quit."  

"What then is a good reason to quit? To my knowledge, you have the right to quit when you realize that... it is not right enough for who you are TODAY."   "Getting emotionally attached to an activity you spent a lot of energy, emotion, attention, or money to obtain reflects what in economics is known as the “Sunk Cost Fallacy”."   

"Do you really want to get to the top of the mountain only to notice you climbed the wrong mountain? Today you can take a new decision with new information."  

"Treat quitting as a lifesaver, as if you only had a couple to use in your lifetime. Stick with something until you realize it is not helping you get where you want."