The phrase "thinks better of" typically means to change one's mind about doing something because one realizes it would be unwise or not in their best interest. Some synonyms for this phrase include: reconsider, revise, reassess, reevaluate, second-guess, and have a change of heart. These words all convey a similar sense of someone realizing that their initial judgement or decision may not have been correct, and taking steps to correct this error. It's important to be willing to think better of things we have previously decided on, as it shows maturity and a willingness to admit when we are wrong.