In my point of view, the great lecture is the one that each and every student in the class understands it. In order to deliver such lectures, I think the basic step is to get the command over the material that you are going to teach. This really increases the confidence level of the faculty.
The next step is to bring the real and simple examples to explain the concepts. This definitely gives students a clear picture of the topic that you are teaching. However, in some fields it is not that easy to find or construct real examples, in that case faculty needs to prepare his own examples and give additional references books or articles that help the students.
The other important things that the faculty should really care are voice should be clear and reach every corner of the class room, vary the voice levels accordingly, maintain eye contact, ask questions during the lecture to make sure that every one is understanding and finally dress well.