And before you make any assumptions about me.
I have milked this cow directly into my coffee cup a number of times.
There are a number of hygiene concerns,
1 ecoli is part of a normal healthy cows microbiome, it lives on their skin, if you get it in the milk, the milk isn't safe.
2 shit, if shit gets in the milk, it's not longer safe.
3, and this is the main reason pasteurisation is so popular.
Infections, most dairy farms in USA Canada Australia etc. are full of mastitis, they don't clean anything properly, one cow with an infected udder gets milked, the next cow to get milk gets the infection, all the puss and blood goes into the milk, without pasteurisation that puss and blood would also make people sick.
