Deaths intended to be big emotional moments but end up falling flat as a result of writing or acting

Brian Griffin (Family Guy) - A blatant ratings grab, Brian's death was so manufactured and overtly emotionally manipulative that it fails to get the desired response, especially upon rewatch since they brought him back within a month rendering the death literally meaningless.

Danny Pink (Doctor Who) - Danny was the love interest for Clara Oswald, his sudden death is the moment where Clara finally stands up to Doctor but his character was so poorly developed that nobody really cared about his death.

Mary Corleone (The Godfather III) - an infamous cse of nepo casting, Sofia Coppola was brought in as a last minute replacement when Winona Ryder had to withdraw from production and her lack of acting experience drags down the entire movie, in her climactic death scene Al Pacino and Diane Keaton try their best to sell the scene but they might as well be acting opposite a plank of wood.