In teaching, what are the advantages of using slides over doing board work?
I am a student and I much prefer lecturers who write on the board than the ones who use slides.

Profs using slides generally go into loop mode where they have the objective of going through all the slides before the end of the class. As such, profs tend to go in a very fast pace.

Writing on the board brings some dynamism to the lectures. The lecturer tends to pace himself much better, and students are then more encouraged to ask questions as they go along. 

Also, having students write notes help them become more active and aware during the lecture.

In my experience I've seen lots of profs who just read the stuff from their slides without elaborating any further. The students then tend to fall asleep since they know the lectures are basically in the slides. 

Also, I have the impression that profs using slides are lazier in their teaching, in the sense that they don't even review the slides they are about to present before the lectures.