This is a book about air accidents written from the point of view of the crash investigation agencies. It describes the investigations and the conclusions reached and subsequent events.
This means that it is not really a book about air accidents but, neither is it a book about air accident investigators. The book does describe some aspects of the investigations but it does not really analyse the work of the investigators.
It is really a collection of annecdotal accounts of a number of accidents that were featured on an associated TV series.
The books title is rather misleading. Nowhere does the author attempt to say "Why air safety is no accident" rather, he just reports on the investigations.
I do have one major caveat about the factual accuracy of the book. The author's description of part of the Tenerife two-jumbo accident is at odds with the other descriptions that I have read. In particular, he states that there was some confusion about what the FO of the KLM aircraft said as it commenced its take off roll. The author states that it was not clear from the tape whether the FO said "we are at take off" or "we are taking off."
According to other reports of this accident, the FO clearly said "we are at take off" but they made the point that, in the grammar of his native Dutch, the meaning of that phrase is the same as the meaning of the English phrase "we are taking off." Indeed, the author fails to appreciate that this accident led to a major change in the approved phraseology for radio communications between pilots and controllers.
On the positive side, desipte its shortcomings, the book is interesting to read and I certainly enjoyed it.