well, I would look at it this way, had noone been there you would be doing five pallets and zoning. That is better than one pallet and zoning. Is he dependable and show up for work? Is he doing the best that he can do? (not everyone works the same way, my best may be four out of five pallets, yours may be eight out of eight pallets) it doesn't mean I am not doing the best that I can do, it means some just can do better than others. I am NOT a speed stocker, but I can guarantee you when it is done it is done 110% right, noone has to go behind me and fix anything. If I am doing mods I deal with the deleted merchandise (find a place for it) when I am doing the mod, NOTHING is ever left in buggies and taken back to find a place the next day; each 4 foot section is done 100% (labeled, flagged, stocked as it is done). That is the way I work.
I try to give people the benefit of the doubt; does he always do this, did he just have a bad night, or is he doing the best that he can absolutely do. I would keep him, there is a chance to recover him from the pits. Don't know about the coaching, just a verbal or a written? Maybe just a warning this time, unless it is a repeat.
Just my humble opinion.