I believe that many teachers can relate to this quote. It seems like something within us simply cannot resist correcting mistakes. They cause us near-physical pain and we often jump down our students' throats interrupting their speech and offering the right option.
In contrast, there are those who do not correct mistakes at all pointing out that students will naturally develop their language and that fluency (speaking without hesitation) is more important than accuracy (speaking without mistakes).
I personally believe that, not unlike other areas of our lives, the truth lies in between. My ICELT tutors have taught me to note down both successful and not-so-successful samples of the language my students use and provide feedback at the end.
Why is this a better idea than correcting every single mistake as they speak?
Developing our students' fluency and, more importantly, their confidence in a foreign language IS crucial. This is particularly true if you work with adult students who have achieved great heights in their career. You basically work as a half-time (at least) therapist. They come to you with their luggage of insecurities and prior learning experience, which is more often than not negative (otherwise, they wouldn't have come to you, right?). This is why, in addition to actually teaching them language you need to inspire them and assure that it is, indeed, possible for them to master the language. As you might have guessed, constantly interrupting them to point out their mistakes is not only rude but also undermining. This is a great way to shut them down and convince that they should not ever speak again.
Why is this better than not correcting at all?
For one, your students do expect you to correct their mistakes and facilitate the learning process. If they don't, a speaking club (a great tool, by the way) will be a better option. Next, imagine a fitness trainer who, trying not to discourage their trainee, says: "All good, man! Keep doing that!", while, in reality, the person is doing it all wrong. You might argue that language is not the same as health, but, you see what I mean, we do not want permanent damage, AKA fossilised error, do we?
How DO we do it?
As I said, my tutors have taught me to take a sheet of paper and separate it into two equal parts. You then become the chronicler of the lesson, noting down some great language samples, their mistakes and the new words that pop up during the lesson.
This is great advice and I hope you can follow it. I don't (sorry!). I do follow this instruction while analysing the recordings my students send me but not in class. Instead, I give the encouragement and celebrate their achievements by giving them thumbs up, a big smile and uttering exclamations such as "Good English!", "Bravo!/Brava!", "Well done!", etc. In addition, I write down or type in a word doc the new words (marking them as NWs), grammar and pronunciation mistakes (code marking - pron.). I am aware that they do know at least some of the words they could not remember and are able to correct their mistakes. This is why in order to boost their self-esteem and to make my job easier I give them a chance to "redeem" their performance with the following steps:
1. I either say the NWs in their native language or provide a definition to see whether the new words truly qualify as such. If they don't, I cross them out and encourage my students pointing out that they do have a decent vocabulary and all they need is more practice. If they don't, I circle them and then create a Quizlet set naming it as The Unstoppable Warriors New Words 19/04/2019 (if it's a group) OR Poghos Poghosyan New Words 19/04/2019 (if it's an individual student).
2. I write down the mispronounced words on the board and ask my students to read them. If they do it right, great! If not, I either correct them and ask to do it all over again or add the words to the Quizlet set.
3. Where grammar mistakes are considered I have two options:
say the sentence or phrase in their native language and ask them to translate
read or write the phrase/sentence with the mistake and ask them to spot what's wrong
This is done to see whether this is a "real" mistake. Once an error has been identified as genuine there are several ways to work with it:
explain it on the spot
note the topic it refers to e.g. reported speech and explain it at the next lesson or send them relevant resources
add the entire phrase/sentence to the Quizlet set
Although I try to note down their mistakes without interruption as they speak, my students have developed a curious reflex. Once I pick up my pen, their brains register that something is wrong. They then start to search hectically for the mistake and often do manage to correct themselves on the spot.