init value change gets triggered when the initial value is bound to a variable and you change that variable.
if you want to execute a workflow when the user clicks on the checkbox and changes the value you need to use the on change trigger.
it’s easy to get confused because a common pattern with input is to bind a variable to the initial value and update that variable with the on change trigger
that’s because the “init value change” is triggered only when the bound initial value is changed.
in your case it will trigger if you change the value of the variables used in the calculation in a way that results in the opposite value.
if you want to trigger a workflow when the user manually checks/unchecks the checkbox you need to use the “on change” trigger.