Really depends on how the game handles it. (Among others) Rayman does a great job at this: parts aren't too long and don't faff about failing. There's hardly a second between failing and the ability to try again. It needs good controls and needs to ramp up the difficulty smoothly.
But once a game does this, it becomes better than an average or even an easy game. On that topic: some Rocksmith tracks want to make me go hide under a blanket. But because I can practice all sections of all songs at my own speed and difficulty, I can just spend hours practicing to suck less (btw... One day I'll 100% those iron maiden songs... In about 1000 years, but I'll get there :-P )
But once a game does this, it becomes better than an average or even an easy game. On that topic: some Rocksmith tracks want to make me go hide under a blanket. But because I can practice all sections of all songs at my own speed and difficulty, I can just spend hours practicing to suck less (btw... One day I'll 100% those iron maiden songs... In about 1000 years, but I'll get there :-P )