When I read the requirements for elders in 1 Timothy and in Titus they are pretty much the same. However the one that stood out to me is in Titus 1:9, "He must hold firmly to the trustworthy message as it has been taught, so that he can encourage others by sound doctrine and refute those who oppose it". ( NIV) The flock that the overseer has been appointed to lead must set the example of believing and living what they are preaching. The overseer can't preach one thing and live their lives a different way or worse not trust what the scripture's are saying. It doesn't mean that he/she has to know everything or claim to know everything but they have to trust in what God is saying through His Word.
If they can't demonstrate that they rely on God's message then they will send a conflicting message to their flock. In order for people to know that an overseer trusts the message that he/she is delivering the people must be able to see that he/she are living their lives that way.