What's the Difference Between Output and Completion?

People that think output equals comprehension are wrong. Some people have really good output and their comprehension is a lot lower than you would expect. It's like, how can I trust that I know what you're talking about if you can't actually put into practice what you'retalking about? "I get why it's toxic," he says of update videos in Esperano. 'It has to be another language'