I love Maya Angelou, but one must remember that poets generally make up the worst sort of common knowledge and wisdom. She says: "I've learned that people will forget what you said, people will forget what you did, but people will never forget how you made them feel."
What's wrong with this? It's just feel good pap. Scientific research shows us that memories of feelings are among the most malleable. That how we think we felt about someone or something in the past is very much dependent upon how we feel in the current moment. People will not only forget about how you made them feel, but they will tend to get it completely wrong.
Never trust a poet to communicate actual knowledge, other than knowledge about poetry itself.