Often I encounter situation where:-

1. test cases in problem statement examples pass
2. smaller test cases with < 100 elements pass
3. Larger test cases with >100 elements fail

In such cases it is extremely hard to debug and understand the root cause of the problem. Is this an intended design to make the problems more difficult or is are these unforseen cases where there is no small test cases for certain edge case(s)?

In case of latter, would contributing a smaller test case qualify for 100 leetcode points?