Exigence is why the author decided to make his project. What things or acts made author write. For example, I wrote my lab report based on the New York City bus system, because I am using it a lot and sometimes it is very hard to be on time with such a bad traffic as in NYC. The subject of the lab report is very relative to my life. That was my exigence. I think that it is good when author has a strong exigence towards the subject, because it allows him to write more fluent in some way and to explain his ideas with passion and truth. For the audience it is good as well, because they will see that the author is not neutral about the subject.