Take Harry Kim. He's been an ensign for 7 years--actually I understand why he would pissed. But on the other hand, I understod they were in abnormal predicament.
They wewre stranded with a ske;eton crew 70 years away from home. I woiuldn't expect a promotion during that period.
He was worried he would die out there and on his gravestone it would say "ensign" and he would be 47 years old.