Answer:
A sunk cost fallacy
Step-by-step explanation:
The sunk cost fallacy states that people tend to continue a behaviour as a result of previously invested resources, even when the continuance of the behaviour brings them no benefits, or even harms them. In this case, Mehmet wants to stay to watch the movie because he already made the initial investment of purchasing the tickets. However, this is another waste or resources, as he is now wasting time in an activity that he does not enjoy.