I think this means that the dead wood (useless/burdensome people or things) are the same anywhere they are. So the useless are useless not only in one situation but useless all around.
Explanation:
Example: He cut the "deadwood" from the group. So he is getting rid of the useless people in the group.
A high school in the UK has banned expensive designer coats in an attempt to stop "poverty shaming." Students who can't afford to wear designer coats "feel stigmatized, they feel left out, they feel inadequate.'' This proves that school should ban branded clothes
