The inevitable cycle of the sonic the hedgehog fanbase, where a game will be once considered amazing or terrible, but then the opinion gets a complete reversal by being too "overrated" or "an underrated classic".
A few examples of the Sonic Cycle:
Sonic Unleashed came out and was panned badly, nowadays its considered one if not T H E best sonic game by a large part of the fanbase.
Sonic Adventure 2 came out and got very great scores, and some even considered it a masterpiece, but people considered it overrated for such a long time that its considered a terrible game...
The next victim of the sonic cycle might be sonic forces, the newest sonic game, which was panned by polygon a.k.a. Diet IGN.