The author, a professor of engineering, recounts how she overcame her initial struggles with math and science to become proficient in these subjects as an adult. She attributes her success to a combination of memorization, repetition, and practice, which allowed her to develop fluency and understanding. The author argues that the current emphasis on conceptual understanding in education can be misleading, as it may lead students to believe they understand a concept when they have not yet internalized it through practice. She suggests that a balanced approach that includes both understanding and practice is necessary for true mastery of math and science.