Aras Itemtype server events behavior

Hi all,

i am trying to understand behavior of server events attached to an Itemtype,

Let us say "add_prefix_to_document_name" is a method which is present on onBeforeGet event of Document itemtype,
now, when i load any Part  for ex : ABCD is a Part, which contains 25 documents attached to it,
so, the "add_prefix_to_document_name" should get called for 25 times but it is getting called only once... why is this happening ?
is my understanding wrong about this ? please help

Thanks in advance,