Almost every fit complaint about custom club kit traces back to the same afternoon: a sizing session held standing up in a clubhouse.
What the cut is doing
The back panel is longer than the front so it still covers when the rider is bent over. The sleeves are set forward so they do not pull across the shoulders in position.
Standing up, all of that reads as slightly baggy at the back and slightly tight across the front. The jersey is not wrong; the position is.
Why riders then order a size up
Because in the mirror the correct size feels snug and the next size up feels comfortable.
On the bike that extra size flaps at the front, rides up at the back and loses the gripper’s hold. The rider concludes the kit is badly made.
The fix, which is free
A sizing set, tried on the bike, ideally on the turbo or leaning on the bars.
Ten minutes per rider removes almost every exchange, and it is the single highest-value thing a kit officer can organise.
The other half of the answer
Do not buy race fit for everybody. Most club members are not racing, and a true race cut on a rider who is not racing is simply uncomfortable.
Mixing race and club fit on one order is normal, costs nothing extra, and is the difference between kit that gets worn and kit that does not.