For students going to a particular university, math SAT scores are inversely correlated with verbal. If students had a higher math SAT and a higher verbal SAT, they'd be at a better school (and worse math + worse verbal = worse school).

For debtors inside a certain grade, it looks like employment history and other creditworthiness metrics are inversely correlated. So I suspect that it's less employment length being an anti-signal, but rather within the grade people with short employment length have compensatory advantages to stay in that grade.