Awareness of severe weather saves lives. That is the only real justification for our interest in it. I would imagine that the death toll yesterday in the Ohio valley in the pre-warning era might have been 100-300. So far it seems to be less than 50. So that means 50 to 250 people are alive today because they knew a strong tornado was coming and made the right decisions as to where to go to survive it.
Just bookmark this reference for all the inevitable "why do you track severe weather?" posts in the future.