I did get immersed in the competition aspect in Duolingo where scoring XP was the goal. but having had problems where my scores were, frequently, not recorded at the end of an exercise, I gave up, and now enjoy the learning process. Reading the comments is part of that learning, Duo has provided the vehicle. If at the end of an exercise it doesn't record my score, I just do the exercise again. I am still learning in doing so.