Storyline Branching Variables not Working?

I agree with MichaelHinze​. Trigger order matters. A slide can't run a trigger if the program has already jumped to another slide. A "jump to" trigger should always be the last one in any series of triggers with the same "when."

Whenever you're using variables—especially across multiple slides—it's helpful to show the variable references in temporary text boxes. That lets you see whether a variable changes as expected.  

By the way, adding 1 to a number variable works to track completed topics—as long as the user doesn't repeat a topic. If they do that, the number variable would reach the total you're looking for but without having viewed all of the topics. Another way to track topic completion is to use a T/F variable for each topic. (See: TIP: Create a Custom Menu Slide | Articulate - Community)