Is it True that All AEE and EE has a 5% chance to ADD nothing at all?

I've never heard of something skipping bonuses before recently when my friend told me that her AEE on her Tyrant Boots had failed to add a single stat.

So maybe it is just Tyrant? Of course, this is just from hearsay and not personal experience.

I've had an EE not add stats on a GDK when my shad was in his 12x, I'm surprised it isn't common knowledge that not all passed EEs add stats.