I remember having read in "The Art of Doing Twice The Work in Half The Time" by Jeff and JJ Sutherland that you are supposed to discuss sprint performance problems with the entire dev team, instead of discussing the problem with one developer alone.
However how about this situation:
There was a team and one dev was underperforming.
Some developers reported, in private, that the likely causes had to do with commitment, discipline and maturity issues. The other developers were irritated with the underperforming individual.