Daydreaming -- does it decrease screen life? Does enabling daydreaming (display a clock while charging, i.e. never turn the screen completely off while charing) affect the life of the screen in any significant way?
As life of LCD screen is measured in hours of its usage, keeping screen turned on does consume some of its life hours.

But, average life of LCD screens range from 30,000 hours to 60,000 hours, so I don't think it would a matter to you.