Maybe the answer is not what people want to hear. This lady that possessed such great beauty never aged. By passing away at 36 she remained eternally beautiful. There is also a vulnerability that seeps through images of her.
The only ironic thing is that when models recreate her look today- they are so retouched that no vulnerability ever seeps through. This makes the images lack a certain Junoesque - This makes Monroe beauty unique and will so forever more.