the user will execute it when they want to open a file, select an item, open a sub-menu, run a script etc. The double-click is a deliberate action i.e.
The right-click button can only click once but the left-click button can click once to select an item, and it can be used to click twice to execute a function, normally to open or execute something. A mouse has two buttons for clicking and the click executed from each button has a different function.
