Ok let's be honest, due to the maximum contract length of 7 years whole graduation idea is kind of impossible in Korea, well unless the contract would be for example only 5 year long, and being a graduation member would mean that you receive a new contract/contract extension offer.
But ok fork that, but what about KPOP group with proper election system? Each year in summer due to fan voting/fan fundraiser the members would be ranked, similar to what you see on the graphics below. Think of it a bit the same way as when fans are doing fundraising for their fav idol's birthday. Just here you have a bit of competition added, with either #1 being crowned as Queen, or like it usually is in the case of SNH48 (which is an example here) top 3 members get a crown, cape, trophee, etc. (all other members also get a trophee).
Of course, there are a lot of advantages here when the group is big, each year election might bring a change in the "center" or "face of the group" position.
I'm curious about your opinions about the whole case. Waitin.
or like here
Also of course in the case of SNH48 this is very big group with many sister groups, and sub-units within them so because it's like 200 members or more in total, then those ranked in top 16 usually get an additional promo by being in special MV, etc.
