Why you do that to me?

Question

sololearn in your challenges there are questions about things i didn't see in the courses !!!

Answer 1

That's absolutely true. And that hurts when you lose much xp because of it. Still, try not to be angry about it, but better learn the concepts that are in challenges but not in courses. The more you learn, the better you are in programming
Best of luck

Answer 2

Agree. IMHO, though, many of those quizzes are submitted and approved by the community, not by SL itself... I tend to dislike quizzes that are far away from the course's contents.