i'm not really sure, but i think it also has something to do with fret spacing. I mean, just thinking, you can fit 24 frets with more space between on a 26" neck than a 24" neck.
Ibanez Xiphos XPT700
Laney VH100R
Epi Les Paul (SH-1 '59 neck, SH-11 custom custom bridge)
lol we have the same avatar NICE! I'm not sure how they measure it, but i believe the biggest difference for example between 24.5 and 25.5 scale length is string tension. When tuning down the 25.5 scale guitar string tension will be better.

Fractal Axe-Fx Ultra
EBMM JP7 Dargies Delight II
Manuel Rodriguez C Cedar Top