Why does every film about Lennon have to end the same way?

Ah good, Mr. Genius, then enlighten us about how Chapman was the capper to the federal government's battle with John Lennon. I'm afraid I'm too stupid to grasp how Chapman was the ultimate element of the federal government's legal battles with John Lennon. When you and your family are sitting around telling some story about your grandmother, I'm sure you always end it by mentioning how your grandmother died. How digusting for me to even suggest that that was not a necessary thing to mention each time your grandmother comes up! Sure it was nice how she baked apple pies for you each time you visited and sang you songs from the olden days but mainly she died.