I would like to know were people rank him. I am thinking most the votes will fall anywhere between 3 and 12 but let's see.
11 really only had 8 good wins and most of them against past their best fighters only one of who could be considered a real heavyweight.
I think the biggest arguments for having Marciano top 5, are: 1. His paper 49-0 record, he's the only retired HW world champion who never lost. 2. As per this thread - https://www.boxingforum24.com/threa...best-fighter-on-the-planet-most-often.701311/ - he beat the highest ranked HW in the world other than himself, more times than any other HW in history, aside from Ali and Louis. Beating the next best HW in the world more often than anyone outside the clear 2 x greatest HWs of all time, whilst never losing, he has a good argument for being pretty high up on the list after Ali and Louis.
For me Rocky is in the top 5, his era was not one of the best for heavyweights and all the best fighters he faced were no longer in their best days, it's true. But Marciano never lost, overcoming difficult moments in matches with Walcott, Charles (both beaten twice) and Moore and he beat a very good contender like LaStarza twice.