1. Arthur Melo
It's hard to make it onto a list like this one as a loan player, but not impossible, and Arthur was just able to get the job done.
He came in at a time of need, and contributed absolutely nothing to a thin Liverpool midfield that was somehow made even thinner by his arrival at the club.
Arthur never made a Premier League appearance for Liverpool, and played just 14 minutes of Champions League football.
He never did anything negative on the pitch to complain about, but his total unavailability throughout his one-year stint with the club is borderline unforgivable.
Insult is added to injury by the fact that he was extremely prolific for Fiorentina throughout their jam-packed 2023-24 fixture schedule, providing the support he wasn't able to at Liverpool.