In what circumstances have defendants failed to establish ineffective assistance of counsel?

We also determine that defendants have failed to establish ineffective assistance of counsel based on trial counsels' failure to object to CALCRIM No. 250. Since we have concluded that the trial court's error in giving CALCRIM No. 250 was not prejudicial, we further conclude that defendants fail to show a " ' "reasonable probability that, but for counsel's unprofessional error[ ], the result of the proceeding would have been different." [Citation.]' [Citation.]" (People v. Lopez (2008) 42 Cal.4th 960, 966.)