Why so few points on this one? Where did I go wrong (or did I)?

Why only 40 points on this one? Where did I go wrong (or did I)?

Hi dswansonsb, it looks like you did a fine job on that piece.  Our score system is usually pretty good but every once in a while it messes up.  Scores are based on how your results compare to other peoples—so if the other people missed a branch on this cube, and you didn’t, you might get fewer points even though you were right.  We’ve got safeguards in place to prevent this from happening, but every once in a while something like this comes through.