Ineffective backGroundColor

[Richmond]

Why, if I set the backGroundColor of an object using a 3 number code (RGB)
am I able to do a:

put the backGroundColor and get those 3 values,

while if I set the backGroundColor of an object using a colorName
am I UNABLE to get the RGB values using a:

put the backGroundColor ???

AND,

what is the point of the 'effective' in

effective backgroundColor

????

Richmond.