One time I heard a song and it was catchy and fun to sing along to. The lyrics, a bit confusing and aimless, didn't really matter. A few years later I listened to the same song again and was amazed at how profound the lyrics were. They were provocative and really touched me. It was as if the musician knew what I was thinking and found a different, sometimes more precise, way of expressing those thoughts. Or sometimes I'll hear a song and I will put a certain meaning to it. Then later down the road, the song meaning will vastly transform for me. Taking on a whole new face with a different story. I think I could say that I had experienced more in life, therefore had more to relate the music to.
Then it happened with some other songs... and more and more.
Life experiences define your music.