Why trauma to the base of the brain is often much more dangerous than trauma to the frontal lobes?

the frontal lobes mostly control motor skills and personality, which are less important for survival than the other parts of the brain. in the back specifically there is the reticular activating system which processes and interprets stimuli. trauma to the R.A.S. can cause it to misinterpret the information it gets, essentially rendering the entire brain useless.