FrozenNorth
Hero
A medium character with a strength of 8 could lift 120 lb, so, depending on race, they might have difficulty. As they should. You wouldn't expect weakings to be able to shin up a rope without a chance of failure. I know I can't climb a rope.
My understanding was that we weren’t talking about a “chance of failure” (which an Athletics check represents). We were saying that centaur PCs were unable to climb due to their weight.