Why does the factory keep the old value of the variable when accessed outside the angular context?

Question

JavaScript

Good afternoon!
Have a factory

app.factory('headerMode', ['modal2', function(modal2) {
    var _mode = 'init';
    return {
      setMode: function(mode) {
        _mode = mode;
      },
      checkHistory: function() {
        if(_mode === 'history'){
          modal2.show();
        }
      },
      checkParameters: function(){
        return _mode === 'parameters'
      }
    }
  }])

D controller hangs $watchwhen the variable is changed, it calls the above- setModepresented factory, the factory itself serves to exchange the state of a single component, setModeit is called only in the 1st place.
If you inject the factory to another controller, and call checkHistoryor checkParameterseverything is fine, the value is _modeexactly what came in setModeearlier, or 'init'if the state did not change.
But if called outside the context of angular

angular.injector(['ng', 'myapp']).get('headerMode').checkHistory()

or

angular.injector(['ng', 'myapp']).get('headerMode').checkParameters()

inside the factory _modeis always in state 'init', even if we changed it via _setMode
Is a new instance of the factory created for my call out of context?