Monitor Image is Lighter (Darker) than Printed Image - Why?

Lightness/Brightness is always a complicated issue when comparing a display and a print. The different nature of emitted and reflected light makes it difficult to produce an exact match. This can usually be done only in a very controlled environment where the luminance of the display and the reflected work are matched. If the monitor is very bright but the room lighting is dim, the printed piece will appear much darker. If you use a lower brightness setting for the display and view the print under very bright lights, the problem will reverse. How much of a difference is seen will depend on the situation as well as the content of the image. To resolve the problem I would first try to keep the display and viewing light at a similar level. Then I would make sure I have an accurate display profile created with a colorimeter. If there is still inconsistency, I would probably edit the printer profile first, unless I am certain my display profile is flawed. Of course any editing of the display profile has to be done visually, so you are back in the trap of not having an objective measurement.