No matter how many times we heard the same thing, endlessly, that doesn't determine anything about our level of understanding. One thing for sure, even if you attended the same thing a thousand times, the only message always revolves around our responsibility to the people around us. I'm not the right person to preach about this but you can't run away from a responsibility, especially a responsibility from God.
At the Day of Judgement, people will question on the reasons why did you choose NOT to tell them? When it's pretty clear that we are responsible for everyone we abandoned and ignored, and for everyone who're acting wrong and we just let them be. Nobody wants to be blamed for the sins others did. So tell, and don't just sit there and act like you don't know. No matter how little you tell others, at least you're doing it instead of sitting there ignorantly.
But what if we felt like we've sinned a lot that we're not in the best position to tell others to do good. That's what I felt. Every second every day. The least we could do is start changing ourselves to the better. Because the Prophet saw told us, celakalah orang yang hari ini sama dengan semalam.