German Tree Bugged
Hi! I've been having decaying problems with my German tree lately. All of my most recent skills I've learned quickly change from gold to various colors. For example, a couple of hours ago I strengthened the "Communications" skill and it has already degraded. This happened for a couple others too. Thanks for any fix! :-)
If I understand you, this is normal. Duo estimates a "strength" for each word/concept you have learned, as a function of how recently you've seen it and how often you get it right/wrong. The skill strengths are simply the average of the individual words/concepts in that skill.
So, when you practice a skill you probably won't see all of the words... and a few hours later some of the other words might degrade enough to drop the average from 5 bars down to 4 (especially if this is a newly-learned skill and you haven't seen the words very often). Alternatively, you might have gotten several words wrong every time during practice, so Duo strengthens them because you've just seen them, but wants to drill you on them again very soon after.
I agree that the way this is communicated in the interface is a little confusing right now, and we're thinking about how to do it better.