A telepromter can be a great asset when there is a lot of script material to get through. Often called by one of it's brand names Autocue (just like the Hoover / vaccum cleaner effect) - a teleprompter lets the presenter read the script while looking straight into camera. This is incredibly useful as a presenter can concentrate on presentation performance rather than remembering their lines.
Placing cue cards to the side of the camera often results in a "shifty" distracted look on the presenters' faces.
A telepromter increases your studio cost not only because of the extra equipment but because of the operator needed. If your production has more than a few script lines to camera for the on-screen talent it's well worth the extra cost for the time it saves versus time used with presenters' forgetting their lines.
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