Depends on who you ask. Some under rate him because of when he fought. Others like me think he's arguably the greatest heavyweight of all time, a top 10 ATG and almost a picture perfect fighter. His offensive pressure was unbelievable, he threw perfect combos focusing both upstairs and down. His footwork to get into position to land those combos was a thing of beauty. Speed/power with precision and accuracy.
Neither he's rated correctly either #1 or #2 best HW most go with Ali #1 and Louis #2 it's debatable resume (Ali), Longevity and defenses (Louis), either way almost no one ranks him lower than 2.
In my opinion he's the best Heavyweight of all time. It seemes that most people have him top 5. In this regaurd he's fairly-ratted. However, like all heavyweights he dose not get the respect as an all around boxer. He might not have been flashy but he was very good, or for his acomplishments. How many boxers won 26 championship fights in a row? In this rguard he's underrated.
Louis was the very definition of economic, he did just enough all the time and didn't overexert himself. Which is also something I loved about him. Though when he had you hurt you were basically ****ed, kinda like a hit man I guess... efficient and deadly in one neat package :think
Best heavyweight champion of all time. Look at the man's record . Joe never wasted as much as a feint in the ring. Quite often underrated !