Learning Software Engineering does sometimes make me really confused...

The lecture slides are extremely difficult to understand (because they apparently were written in English by a German, but that's not what my complaint is about). Therefore, I needed a good book in order to understand the course. We were given i literature list of nine different books, and in the library I was able to find the one on the 8th place.

To begin with, I did not expect much of that book. I thought it would mention some of the topics we have had. But it actually covered most of the essential parts of the course. Moreover, many examples (examples is always the most illustrating tool in computer science), given in the book were exactly the same as those in the lecture slides.

That confuses me most. Are there only standard examples for all the occasion in Informatics? To the authors lack the imagination to create something by their own? Or did some of them simply missed the point themselves, and hence are only able to rely on the research made by others?