This is the 13011th most frequent Korean word.
동기라서
"동기라서" means "because (we are) peers/classmates" or "because (we have) the same motive."
동기라서 is used here to indicate a reason based on shared circumstances, specifically being classmates in the same academic department.
우리는 같은 학과의 동기라서 친구가 되었습니다.
We became friends because we are classmates in the same department.
동기라서 conveys the reason or cause for the competitive relationship, stemming from being peers.
동기라서 서로 경쟁하게 되는 경우가 있기도 해요.
Sometimes, we end up competing with each other because we are peers.
동기라서 explains the enhanced understanding due to the shared experience of being peers.