The easy and cowardly thing to do is shift blame aka pass the buck. I think it’s majority of people and cases.

I respect the person who actually takes responsibility and OWNS their error/failures. It shows bravery and maturity. And willingness to admit their mistakes and grow from it.

Exams and test scores are highly correlated with socio-economic status, race/ethnicity, class and home background of the students so there is bias.