Corbyn is such a failure:

Tories extend lead over Labour to 10% despite chaotic week

Corbyn and his Labour party were always going to be ineffective because Corbyn and some others in Labour were essentially pro-Brexit though they weren’t big campaigners for such.

This is the problem with the old socialists, who are inflexible. It’s why they hate the likes of Clinton and Obama, because those two were triangulators. But triangulators, not ideologues, are people who can get things done.