Silverstripe reload page

Silverstripe Version: Silverstripe 4

Question:
I noticed something I don’t understand. If in the init () function of PageController.php I write to a file, it always writes 4 times.
So I did the same thing inside a function called in one point of the Page.ss and it always passes 4 times.
How come it seems that Silverstripe throws out the same page n times?

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