plugin retrieve message is fires more than once

Hi experts,

This is for Dyn crm 2016 on premise.

I created a plugin and registered it on "account, post, synchrone and retrieve"

when I open an Account form the plugin is called 3 times and if i refresh the account form it is called 6 times. 

Why is that , I expected it to be called only once?

best regards henrik

--- Best regards Henrik Skydtsgaard