To be fair, SBK-08 makes some effort to be accessible. It has instant action and quick race modes, while the handling by default is a little more accessible than it is in MotoGP - you're not being asked to handle the motion of bike and rider simultaneously straight off. Even so, with the realism settings dialled down and all of the driving aids switched on this still isn't a game you can pick up and play in the way you can, say, a Forza 2 or GT5 Prologue. It takes time to get used to the less forgiving cornering of your bike, and the unnerving possibility that you might actually have to slow down to take tighter bends.
Of course it might help if the driving aids were as effective as they were in Forza, and if the tutorial was actually a tutorial and not a series of racing tests that prove you can't play the game without informing you how you might get better. If you've never played MotoGP or any other bike racing game, you can expect the first one or two hours of play to be a mildly dispiriting experience that fits somewhere between watching your team lose and having someone you've asked out ignore your phone calls in the index of human misery.