It's okay, firstly if your goal is singular than this is fairly solid, if your goal is more complex and wholistic there's a few useful pointers. As others have noticed it's too long, but it's well enough summarised, there's far too much waffle but you can skip over it. As with most of these kinds of books it helps if you know something about the psychology of motivation (see Dan Pink's 'Drive' and Caldini's 'Influence' for approachable, interesting pop science versions), there are a few clangers in here, one in particular is he encourages you to visualise the outcome and reward, this is awful advice, don't do that, it's actually a demotivator it focuses the mind to think about an extrinsic reward which lowers rather than improves motivation (best technique is to visualise the work itself, think 80's film montage but with better music). There's some good ones too in here, don't talk to other people about your plans is good, the other motivator of putting a $100 note on a board and saying "if I don't do X I burn the note" and in general most of the advice is sound enough and there are plenty of resources linked to (though I think he could have gone deeper into GTD apps and the likes rather than simply telling readers to "get an app" also it's always a bit curious when people write book like these but then have little or no online presence).
As a work of art it's lowsy, as an example of it's genre it's mid tier, but with better general insights than most mid-tier books of that ilk. The conversational tone is just about tolerable, gushing references to Richard Branson less so (Branson is admirable in a sort of 19th century huckster selling brain tonic in the wild west made good kind of way, but an awful human being, sleazy, avaricious (notorious for promising donations to charity and never paying up), etc. that he has any kind of good reputation whatsoever is a testimony to the general inability for the media to question the credentials of anyone of power and status (so long as they don't cross certain lines) who reinforces certain ideals (the entrepreneur as Thatcherite ubermench in Branson's instance) and how gullible people remain to pageantry and PR stunts).
One chapter actually opens with the lyrics to 'you'll never walk alone', tempted to give it one star just for that, but that'd be petty, as stated fine for what it is, the underlying principle is mostly sound.