Had a fall at 5mph on ice and the helmet took the impact. 5 minutes later and I had a headache and stopped with my riding partner- who also fell on the ice- and he advised me to look at my helmet. The Gouge mark was at least 1" deep. If I were not wearing a helmet- that would have been my face or my skull. Plenty of offroad spills that have broken a a helmet but have to admit that was at speed.

Imagine your head is a Large lump of Chalk---They used to say water melon but they are soft. Hit the chalk with a hammer- It explodes. That is you falling sideways onto a kerb.

Riding along a trail and an overhead branch. Didn't see it and helmet in 3 pieces and a headache.

I can go on for hours like this. Accidents happen. Broken bones can heal. Concussion can be serious. Fractured skull is- Brain damage is irrepairable.