Nice.
All the time, I just have to forget I said something, then say something else. I reckon if I change my mind but don't tell anyone, if I only tell people my new viewpoint, that counts as contradiction. I try not to say anything too deep, that way if I contradict myself, the hole burned in my reputation is a little quicker to fade.
"How often do you contradict yourself?"
Plenty. I consider the duality of my nature to be one of my defining traits.
"Do you notice, or does someone else usually have to point it out? "
I notice it
"Is advice as to what to do or not do less meaningful from someone who does not follow their own advice"
I wouldn't dismiss it. A lot of the time, they dont have the will or strength to break from the characteristic they are criticizing you from. In that sense, considering they're going through that experience they have all the reason to tell you why its wrong, because they're feeling it first hand. The saying "Takes one to know one" comes to mind.
"or is it better in a sense because they are a living example of what they are preaching against?"
Most of the time, yea
" How often do you find yourself calling someone out for something you are guilty of?"
If it's something I'm guilty of, I'd feel too guilty chastising them for it. If I cared enough, I'd civilly explain my own experiences with the problem before helping find a solution.
Systematic stated: source post
The saying "Takes one to know one" comes to mind.
Oh, that! But projectionists cannot see themselves. It's one of those ever so funny things. ;^)