What ever happened to respect?

I have pondered this topic many times. I try to remember how my parents taught me to respect my elders. I can't remember any specific thing that they did- it's as if I was just instinctively mindful that you show respect to adults. In reality, that probably isn't the case at all. But it's been a part of me so long that I don't know where or how it started. How do I transfer that to my children? They didn't get it instinctively and it drives me nuts when they sass or backtalk. I have heard many many times that children mimic what they see and hear at home. If that's the case then I should have a couple extremely respectful teenagers- but I don't. What went wrong?