I wanted to read an introductive review of the different agile processes before selecting the most relevant for my start-up.
This book is simple awful, boring and shallow.
Reading wikipedia and reading blog on internet, while necessity a fraction of the time required to read those book have made a much better work of both introducing me and discussing on the deeper part of the lean methodology.
Obviously, I advice to skip this book and make your research on internet if you need an introduction or read the reference books of the domain if you want a true mastery (Lean Start-up, Scrum, etc.)
This one will only bring you shallow advice like "you need to motivate your team to accept 6sigma", "you need to make it work" (yes).
Sorry but not for me.
PS: the first books on 6sigma are really, really painful to read because it is very badly written with a lot of repetitions. The other a bit better. If you really need this book, choose wisely your reading order.