There's a question in my mind that, why do some people are able to achieve candidate master by just solving 600-700 questions, whereas few are not even able to reach expert after solving 1000+ question, I'm really concerned about this because i have started CP few months back and don't want to go on a wrong path, so I wanted to know what mistake these people do? so that i won't repeat those mistakes. for example https://mirror.codeforces.com/profile/Mr_Frodo, he have solved 1000+ question, and still not able to achieve Expert.

Note : I'm not trying to discredit anyone, just asking so that we can I can learn.