The antonyms for the phrase "notice similarities" would be "miss differences", "ignore similarities", or "overlook likenesses". When we fail to notice similarities, we tend to focus on the differences between things or ideas, which can hinder our ability to see patterns, draw conclusions, or make connections. Ignoring similarities can lead to misunderstandings, lack of empathy, and inability to learn from others' experiences or perspectives. On the other hand, being able to notice similarities can foster creativity, innovation, and collaboration among individuals and groups. Thus, it is essential to cultivate the skill of noticing similarities and appreciating diversity in our personal and professional lives.