Most likely because it implies that there is some sort of "action". Pulsating is not a consistent appearance, as the item would be dim or bright at different times and would need a script to show that happening.

Also, depending on how quickly the pulses of light happen, some would argue that we simply don't allow strobe lights in Elanthia.

-Marstreforn-
Icemule Trace Guru
Halfling Guru