To quote some other person:
They said Sonic Heroes would be like the classics, with its stages divided into acts and more focus on going forward at all times. It turned out to be even slower than the Adventure titles, with a wonky teamwork system and some incredible repetition when it came to completing the game with each team.
They said SONIC THE HEDGEHOG would be like the classics, by capitalizing its name that shares identicality to the Genesis classic. What it turned into was Sonic Adventure when you take out the things that Sonic Adventure actually did right, with the addition of ridiculous new knock-off characters and quite possibly the most glitches I've seen in a game this generation or the last.
They said Sonic & the Secret Rings would be like the classics, with its exclusive focus on speed with an always-moving Sonic. Instead, it turned into a nightmarish experience where you actually have to EARN decent control, accompanied by some indredibly idiotic and repetitive missions with an obnoxious soundtrack to boot.
So, yeah.