You don't passively read the Qur'an. You read it, you think about what you've read, then you implement the teachings. The Qur'an is a book of action that urges us to improve ourselves and the world around us through DOING.
The Qur'an doesn't change, but what we absorb of it on a daily basis does. Our life circumstances and personal experiences affect what we see each time we seek guidance from the Qur'an -- maybe you had a bad day at work, and you find something that tells you to be patient, or something else happens, and you find verses that apply to that situation and provide guidance and comfort. I know I can take away something new from the same verse depending on my mood, what I've been thinking about during the day, and what my day has been like. In this way, I believe the Qur'an is an endless font of guidance and comfort that brings forth the bounty we need as we need and seek it.