Trust computer / Allow device

Hi!

When connecting my 5C thru USB to Win10 computers it shows different alert messages depending on the computer: "Trust this computer?" or "Allow this device to access photos and videos".

To the first one I click on "Trust", then win10 opens the Files explorer showing the Internal storage of Apple iphone device connected but no content is showed.

To the second one I click on "Allow", win10 opens the Files explorer showing the Internal storage of Apple iphone device connected and folder DCIM is presented enabling the access its content.

None of the computers have iTunes. It is just USB connection to win10.

Why those different behaviors?