We've had decades of failed 'sit down and talk it out.' When do we recognize that it's a failed strategy like lowering taxes or communism? Like these, proponent

We've had decades of failed 'sit down and talk it out.' When do we recognize that it's a failed strategy like lowering taxes or communism? Like these, proponents will inevitably claim we haven't tried it hard enough. That's why it doesn't pass the sniff test.