system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why does gorilla glass shatter so easily when you drop your phone but seem indestructible in their demo videos?
gpt
Gorilla Glass is a brand name for Corning's tempered glass.  Tempered glass is very strong when you hit it from the front, but if you make a tiny nick on the edge the internal stresses cause the glass to instantly shatter.

The demos you see always test the front surface and never the edges.  When you drop your phone, it's usually an edge strike that causes the damage you see.