I will only write the idol groups I can think of, except for the ones that already disbanded
DBSK: Hero Jaejoong, Xiah Junsu, and Micky Yoochun left
Super Junior: Kibum, Kangin, Hankyung left
Bigbang: Seungri left
Brown Eyed Girls: ☆
Ft. Island: Oh Wonbin, Song Seunghyun, Choi Jonghun left
SNSD: Jessica left
Kara: Kim Sunghee, Nicole, Kang Jiyoung left
T-ARA: Jiae, Jiwon, Hwayoung, Ahreum, Boram, Soyeon left
F(x): Sulli left
Infinite: Hoya left
Beast (Highlight): Jang Hyunseung, Yong Junhyung left
SHINee: ☆
MBLAQ: Lee Joon, Thunder left
2PM: Jaebum left
2AM: ☆
B1A4: ☆
Teentop: L.Joe left
ZEA: ☆
Block B: ☆
EXID: Dami, Yuji, Haeryung left
Oh My Girl: JinE left
Girls Day: Jisun, Ji In, Jiae left
Apink: Youkyung left
AOA: Youkyung, Choa, Mina, Jimin left
BTOB: ☆
Nu'est: ☆
Got7: ☆
Day6: Junhyeok left
N.Flying: Kwon Kwangjin left
Winner: Nam Taehyun left
EXO: Kris, Luhan, Tao left
BTS: ☆
iKON: B.I left
Monsta X: Wonho left
Seventeen: ☆
Pentagon: Eden left
AB6IX: Im Youngmin left
NCT: ☆
April: Somin, Hyunjoo left
DIA: Seunghee, Eunjin, Jenny left
GFriend: ☆
CLC: ☆
Mamamoo: ☆
Red Velvet: ☆
Lovelyz: ☆
WJSN: ☆
Black Pink: ☆
Twice: ☆
Momoland: Yeonwoo, Taeha, Daisy left
Stray Kids: Kim Woojin left
G-IDLE:
ITZY:
TXT:
The more you scroll down, the more of them are still together.
Brown Eyed Girls are really amazingㅋㅋㅋㅋㅋ
[+][-]
1. [+132][-2] It's funny how ZEA hasn't disbanded or had any members withdraw from the groupㅋㅋㅋ
2. [+89][-2] The withdrawal of some DBSK's members really shook the worldㅋㅋㅋ If compared to idols nowadays, it's like having BTS or EXO divided into two different groups with the ratio of 3:4
3. [+38][-65] Look at Jisoo's top-tier visual among the other female idols in their 20sㅋㅋㅋㅋ
4. [+35][-1] Isn't it obvious? The idol groups in the top are over 10 years old, some of the ones in the end are not even a year old, how can you compare that? Please don't hate on any groups just because their members left. My favorite idol group is listed here and they have some of their members left the group, but not for a bad reason. We still think that they're together and as 10 years have passed, we can't expect them to stay the same or pursue the same music genre forever. They changed and left the group because they wanted to pursue the type of music they want, I hope none of you will hate them for that.
5. [+29][-1] The way there's a star sign next to SHINee's name somehow aches my heart. I hope they'll stay together for a really long time.