In this article, the author highlights five common mistakes people make when performing the dumbbell chest press exercise, which can hinder their chest gains. The first mistake is not using a full range of motion, where individuals fail to lower the dumbbells until their elbows are at a 90-degree angle. The second mistake is not engaging the chest muscles properly by focusing too much on the triceps. The third mistake is using too much weight, which compromises form and technique. The fourth mistake is not maintaining proper alignment of the wrists and elbows to prevent strain on the joints. Lastly, the fifth mistake is not controlling the negative or lowering phase of the exercise, which reduces the effectiveness of the movement. By avoiding these mistakes, individuals can maximize their chest gains with the dumbbell press exercise.