The Shawshank Redemption

I interrupt the regularly scheduled reviews to address an issue that has been eating me up inside. The first time I saw this film in '94, the moment it finished, I thought, that's it! That is the best movie I have ever seen and it instantly became my number one (just a tid bit about myself, I have always ranked movies). From that moment if favorite movie was ever asked of me, Shawshank it was. Then, very slowly, others began to see its excellence, so it was at the top of everyone's list by 2000. Why the delay?