Why do they distinguish between list-mail and individuals' mail?

At 17:51 08/23/2003 Saturday, J. R. Lankford wrote:
>       One of my subscribers tells me "century tel servers all over
>the south keep going down because of the virus activity."  She says
>her tech predicts multiple server shutdowns across the country in the
>next month and suggests we delay an important list activity coming up.