As a long time KC Royals fan, I will tell you that it is worth it to watch the process unfold. It was painful to watch for many years but we could see the turnaround in about 2012 and then the 2014 and 2015 World Series years were a marvelous ride for us.
It has been 17 going on probably 19 years for us Bills fans, but it makes it that much more special when we reach the top. I am discouraged going into this year like many, but will still watch due to loyalty and the interest in the process. Lets hope it works within 4-5 years or we may face another rebuild.