Question about Symbol / Glyph of Warding

Quote from Natrel >>

 Then that "10ft" rule makes no sense and there is no way to resolve how the spell behaves when the glyph is moved within that limit.
They wouldn't have written this rule if they intended for the glyph to be 100% static even after being triggered.

The 10' rule appears to be intended to avoid accidentally ending the spell by jostling it. Honestly, it's not a great solution to the problem of "it's a trap spell, no using it as an offensive spell", as it can still be used for offense with unusual setups and winds up failing as a trap spell entirely by accident (someone picks up the book, puts it in their pack, and decides to read it later. Guess that glyph of warding was useless).

Why are you even assuming the symbol is glowing the full duration?

"Once triggered, the glyph glows, filling a 60-foot-radius Sphere with Dim Light for 10 minutes, after which time the spell ends."

The symbol glows. It doesn't say anything about the symbol KEEPS glowing. Once the aura is created, the symbol has no purpose. 

Which means moving it doesn't matter, it's already spent.