This quote means that people may not remember what you told them, what you did for them, or what you said to them, but they will always remember how you made them feel. For example, if you said something that made someone feel loved and appreciated, they will never forget how it made them feel. On the other hand, if you said something that hurt or embarrassed them, they will also never forget how it made them feel. So, being kind and thoughtful towards others will stay with them forever.