When strengthening, the strength level stays at the same level
After completing a skill, you forget some of the words and duolingo lets you know where you are struggling and therefore you take the strengthening quiz. After I strengthen a skill, the level stays the same and does not increase.
The strengthening is based on exposure to words. If you do the general "strengthen weak skills," sometimes you don't get enough exposure to the weakened words to qualify as having strengthened them. This is especially true if you've had to peek or gotten any wrong. This might be useful for you.
No, I am referring to the individual lessons. You can select the lesson and then there is an option to strengthen that skill. Which I do, but if i strengthen the skill 3 times, the strength bar stays at the same level. I know how the system is supposed to work, I am saying that it is broken.