
I've been a Kpop fan for so long that I'm losing count of the years, but I think I'm going on eleven years now. That being said, this is a topic that I rarely see being discussed properly. Yet it's so important to address in order for us to be able to enjoy the music of our idols without feeling bitter over things like line distributions.
Because a new comeback usually means new arguments over line distribution, and I have noticed that something crucial is usually left out of these discussions.
The Forgotten Fact

When discussing (what a nice word for it) line distribution there is something that I rarely ever see mentioned, and yet it's at the very heart of the discussion: Member Positions.
In a group, everyone has a role. These roles rarely ever change.
This is true for Kpop groups as it's true for other groups, like music bands and even groups of friends.

The drummer in a band doesn't suddenly become the guitarist.
Likewise, the joker in a group of friends usually remains the joker.
It's true for Kpop groups as well.
But as a fan it can be difficult to remember and hard to accept.
The Positions
The usual member positions in Kpop and those that concern BTS are are as follows.
Note: I won't differentiate between Main and Lead as the differences between the two are subtle and irrelevant in terms of this discussion.
Leader
In BTS, this is none other than Rap Monster.

The Leader of the group has the responsibility of the group and serves as the main link between the group and their company. They communicate the wishes of the members to the company and likewise make certain that the group members respect the demands and wishes of the company.
Smaller groups sometimes don't have leaders, but the only circumstance under which I have seen the leader position change is if the Leader leaves the group, and someone else has to step in and take over.
Pre-debut, the Leader may change, as it did for Winner. Song Minho used to be the leader but was unable to perform the duties due to illness so the position passed onto Kang Seungyoon. But this was only possible because they hadn't officially debuted at the time.
Visual
In BTS this our very own Jin.

The function of a Visual is to draw people in with an appealing face.
This will often mean that music videos with storylines will focus on the visual and when a group of uneven amount of members split into pairs, the Visual will usually stand alone. Photo shoots will also often highlight a Visual.
But being a Visual does NOT guarantee screen time nor does it equate to being the face of the group and it's NOT to be confused with being the Center.
As BTS's Visual, Jin was the main character in the music video for Blood Sweat and Tears, and in the highlight reels too. Even for a Visual that's a lot. He isn't the face of the group, but as a Visual he is often given opportunities during group activities to visually stand out, and he is expected to always highlight his looks. Jin does especially well at this, giving himself the nickname Worldwide Handsome.
Center
In BTS this is young Jungkook.

The Center is not to be confused with the Visual which is a very different position! The Center is the one who most often dances in the middle when they perform and who stands near the middle during talks or official events too.
They're usually given more camera time and music videos often focus on them to explain why they're in the Center during performances.
If you've ever watched Produce 101 you will know how crucial a position it is but also how many demands are put on the Center of a group. The Center usually has to be a Lead Vocalist and a Lead Dancer too, in order to be able to hold up the vocals during the chorus and the choreography as well. It's a position that holds a lot of demands, and equally receives a lot of criticism.
Unlike the Visual, a Center doesn't have to be handsome or pretty, but they have to draw people into their performance and excel at many different performance aspects in order to do so.
Main and Lead Rappers
In BTS this is Rap Monster, Suga and J-Hope.

This one pretty much explains itself, doesn't it?
They're in charge of rap.
However, there is something very unusual happening here within BTS!
It's highly unusual to have as many Main and Lead Rappers as BTS do.
Normally two is the absolute maximum amount of Lead Rappers, and often a single Lead Rapper is the preferred ratio, with the rest being Sub Rappers. This would mean that only one person would have a full rap verse and the others would have maybe one or two rap lines, if they were lucky.
In terms of positions this is where BTS stands out as a hip hop focused group.
Sub Rapper
In BTS this is Jungkook.

The Sub Rapper is there to support the Lead Rappers. They can rap a few lines, if a song requires it, but often they will not have more than one or two rap lines, and are there uniquely to support the Lead Rappers.
In BTS, Jungkook rarely raps anymore, but he still sometimes takes on this role in live performances by creating an echo like effect when the lead rappers do their verses.
He also sometimes use rap techniques to give his vocals an extra hip hop flair.
Main and Lead Dancer
In BTS this is J-Hope, Jimin and Jungkook.
