I just come to realize that advising English learners how to learn English language is actually not any different from the disappointment a preacher can be going through.
Whether you are a monk persuading people to believe in Buddha or a christian priest persuading people to believe in Jesus Christ or God, you will fail again and again. The chances of successfully making one follow your belief is slim.
Lonely or lost people come to you to ask if there is a way to make them a happy soul. Lost and disappointed English learners come to you for a secret formula to learn English.
They come and go. What they can take away and use is entirely out of your control.