From what I know about American boxing, way back in the dark ages boxing was done with bare hands without wearing any gloves. Now of course, boxers do wear gloves. Since they started using gloves there have been some modifications on how the punches are thrown. The punching techniques have been changed to make them more effective when you're wearing gloves but if you try punching like that without gloves you can really hurt your hand. That being said, if boxing is to be practiced for self defense it would probably be a good idea to learn how the punches were thrown before they started wearing gloves. Boxing is primarily meant to be a sport and somebody who takes up boxing will probably do so for sporting purposes but if they also want to be able to use it for self defense they should learn how they threw the punches without the gloves since you will probably not be wearing boxing gloves in a street confrontation or some other situation that warrants self defense.