Someone really has to explain to the artist how those stat hexagons work. They're supposed to show the distribution of stats, not the absolute amount. The highest value never goes outside the circle, the others just get scaled down to compensate
I disagree.
If that were only a representation of stat distribution, either the highest stat would always be at the highest point available (distribution relative to highest stat) or they would total 100% (absolute distribution). And it would never help to know how strong a character is, only what their focus is, if any.
At least in games and manga, every time I see one of these diagrams, weak characters have all stats close to lowest (negating option 1) and strong characters have at least one maxed out and multiple others at high or intermediate (negating option 2).
I assume that the borders represent the highest known or measurable value by normal standards (e.g. in real life, 100% strength would represent a record holder in weightlifting), so anything exceeding that is a clear abnormality (e.g. comparing the stat of an elephant with humans as a basis). Of course, that has to be rare otherwise it defeats the purpose of having the diagram at all.
In fantasy worlds, the problem is establishing a base of comparison if you want to know exactly what each "maximum" represents, because you have factors like levels, races, magic, etc. But it is generally pointless. Just use it as a comparison between known characters and forget about what these values represent in absolute. I'm pretty sure very few authors actually think of these diagrams in so much details.