Expected by whom?
How many home networks or even small business networks have competent
administrators?
What is the infection rate for the network at a typical NANOG meeting full of Internet "experts?" What was the infection rate at the RSA security conference network earlier this month?
Although some specific individual networks may have higher or lower infection rates, I haven't see a significant difference in infection
rates between types of networks or industries. For universities with
low infection rates, there are just as many universities with high infection rates. For government networks with low infection rates, there
are just as many government networks with high infection rates.
Would taking the practices from the specific individual networks with low infection rates and using them elsewhere change the infection rate of
other networks?