Many reasons, but let me quote few people who actually declined the "honor": "I get angry when I hear the word 'empire'; it reminds me of slavery, it reminds me of thousands of years of brutality, it reminds me of how my foremothers were raped and my forefathers brutalised."

"An OBE is what you get if you clean the toilets well at King's Cross station."

https://en.wikipedia.org/wiki/List_of_people_who_have_declin...