Broken Blank Utility

I doubt the mechanics of it work exactly like this but here's how I think of it because I've played a lot of D&D in my lifetime. In D&D, there are different shapes of dice you can roll to generate different ranges of numbers. The one most people think of as the "normal" die has six sides so obviously generates numbers from 1 to 6. There are other dice that generate numbers from 1 to 8, 10, 12, or even 20. I think of blanks kind of like those dice.

If I'm using a polished blank, to me it's like rolling a 20-sided die; there exists the possibility of rolling a really high number that is literally impossible to roll with a 6-sided die... but there still exists the possibility that I could roll a 1. And I've done it. I've gotten raw blanks from a 100%-quality item. More than once. It happens. But I have also gotten polished blanks whereas I have never gotten a polished blank from a 96%-quality item. Maybe it's possible but I've never gotten one. So the higher-quality items give me the POSSIBILITY of a high roll, but not a guarantee.

Like I said, idunno if that's how the numbers work in the background, but that's how I think of it based on the limited observations I've made so far and it helps set my expectations.

I hope that makes sense in some way.