German tree versus other trees
Why is German tree twice as big as the Italian tree or others? Does that mean the proficiency level in German, compared to other languages, is higher after completing the tree? Over 120 circles in German course versus 62 circles in Italian or Spanish...
The German tree may have twice as many skills but those skills are less populated than the Italian or Spanish ones. If you look at the number of lessons you can see especially German and Italian being fairly close to each other. (That post is old but the numbers seem accurate). Of course, we can still have the same conversation about Norwegian and Turkish based on that data.