Where did it all go wrong for Sonic Boom?

Sonic Boom was supposed to be the spiky icon’s new beginning, a clean slate on which to build a Western branch. Unfortunately that slate has been well and truly broken after just one title. Big Red Button have somehow managed to build a worse game than Sonic The Hedgehog 06; previously regarded as the lowest point in Sonic’s videogame career. So what the hell happened!? Why is Sonic Boom such an abomination?