Its focus is on teaching and learning, not getting hired at a big company. Hacker Rank / Leet Code / Code Wars are essentially talent scouts. They want to attract programmers who are already really good. Nothing wrong with that, but it's not conducive to learning.
FYI Codewars has nothing to do with talent scouts. It's purpose is exactly the same as yours, except that it has content ranging from beginner to advanced. Did you build your own testing system for this? It seems to be very similar to Codewars.
Looks like it's for those who're coming to grips with the syntax of a language and trying to move to an intermediate level.