If your book is short you have to be parsimonious in your explanations, touch the main results,go from the general to the particular and avoid getting bogged down in inconsequential details. A great example is Landau's Mechanics .
If your book is long you can afford to be more verbose, present more examples and broad the subject as much as you like.Even then there is usually a preferred order to present the material but the length of your book gives you leniency.
This book is the first type but even in the first chapter it just dives into an specific example using SVM without contextualizing the technique. It is like a 100-pages calculus book solving an integral by parts in page 1.
