Speakers who read often lose touch with the ideas behind the words. Listen for pauses. A potted plant will probably move more. There is little energy behind the lectern. Any eye contact is with the text and not the audience.
Some speakers read because they are afraid to try anything else.
Granted there are moments when one must communicate precise policy or company statements. There are also times when the speech must be timed right down to the second, and so a script is used. When you must read, try to sound natural. Here are some additional tips if you must read. Plan for gestures.