Head kick from Ernesto Hoost

Why is it when i see a head kick from Ernesto Hoost he kicks with his foot first?

I have always been told to kick with the shin, Is it maybe that he cannot reach that high with the shin and maybe thinks he'll go all out power with the foot?

His kicks are just so powerfull but i find it hard to get round the the fact that it's footfirst.
Or am i just thinking he kicks alot with his foot to the head.......?