Usually in K-Pop groups, the leader is assigned to most, if not all, of a speech if their groups win an award.
This tradition has become less common over the years as a lot of groups now let other members speak during speeches.
There is this one time that RM of BTS really wanted these specific members to do the speech and not him. The moment was during MAMA 2016 when BTS won the Best Male Dance Performance Group award. He was seen trying to get J-Hope to be the one to accept the award.
This is because J-Hope is considered the dance leader of BTS and is the one that looks over their choreographies. It also wasn’t limited to just J-Hope as he was seen pushing Jimin and Jungkook to the front during the acceptance speech as well.
RM probably saw it fitting that these three be the one that talks on this award because they are the main dancers of BTS and they should be the ones that speak on their dance style.