So before going through the blog, let's consider an example -
Suppose you have gone to a movie with your friend and you have already paid for it before. While watching the movie you understand that the movie is not that interesting...at that particular moment you told your friend to move out of the movie hall, but your friend said: "we have already paid for the movie lets watch it till the end".
our decision depends on us....
here comes the concept of suck cost fallacy.
Sunk cost is the cost that is already been paid for something and can't be recovered.
The fallacy here is that you put in a lot of time, effort, money or love on something. We tend to continue the task even at a loss for ourselves.
again consider an example-
suppose you are perusing some course that you don't want to peruse. You spent in a lot of effort and time in it, but can't complete it until end. Now you want to do some course of your choice but thinking about your past investments & failure.
implies-
whenever you are taking a decision it should not be based on the past cost that you have already incurred, but only on the basis of future benefits that you are going to receive from that decision.
so, whenever someone reminds you of your previous failures, tell them about sunk cost fallacy.