In what way?
Rihanna is the fashion icon.
Gaga is the fashion icon not.
Rihanna has longevity
Gaga does not
Rihanna has global hits that show her versatility
Gaga can't seem to shift without losing fans each era (An xtina tea)
Doesn't Rihanna have more grammy's than Gaga?
If so, Ouch
All of these apply to knee
The lack of self awareness