Watt causes ingrown hair???

There are a few causes.

One cause is that the hair follicle grows inside the pore by growing / being bent inward into the pore..

Another cause is that skin grows over the hair pore, causing the ingrown hair.

Watt causes ingrown hair???

Skin grows over where the hair folicle is. the hair

starts go grow underneath the skin. Then a pocket of pus forms and a red bump forms. Usually you can pop the pus and create a hole for the hair to pop back out into the open. :-)