The notorious "seven-year curse" correlates with when most idol group members hit their mid-to-late 20s.
Following the Fair Trade Commission's 2009 regulation mandating that agreements between artists and companies can not surpass seven years, the seventh year is when several deals expire. The musicians will determine for themselves, within that threshold, to either prolong their contractual agreements or leave.
Sometimes, another agency will get favorable deals from one or two band members; one factor many female artists call it a day. Boy bands typically last longer as they realize they will be well off with wider fan bases to leverage live performances and record and merchandise sales. (via Kpopstarz)
In the situation of girl bands, though, as shown in the examples of Bada of S.E.S., Lee Hyori of Fin. K.L., HyunA of 4Minute, Sunmi of Wonder Girls, Hyorin of Sistar, and CL of 2NE1, female singers appear to pull free and go individually.
Another path that members of the girl band typically follow is professions in the acting. For instance, Girl's Day Hyeri, Hello Venus' Kwon Nara, and several others have grown established successful careers in acting. Such is not always the reality, however.
There have been occasions in which individuals have conquered this curse with success. See the list below to know them!
APINK
Apink would have dissolved after their original agreement. However, the leader of Apink, Chorong, provided them with the sum of affirmation they desired to support the process and extend their contractual agreements.
The Apink members talked about them during the TMI News episode, renewing their Play M Entertainment deals. Chorong encouraged all members to trust her when this finally happened to amend their contractual agreements, as she wanted everybody to extend their contracts.
The members continued to talk about how valuable Chorong has been to them, and how they'd have never been popular if anyone else had become their leader.
SHINHWA
SHINHWA is historically the only band with a more than 20-year career. They have also kept the world record for the longest time a group has been together without dissolution.
After a four-year break throughout their compulsory military service, the members came together and also set up the SHINHWA Company to pursue their original and musical efforts. If that's not a commitment, then we don't know what that is.
SUPER JUNIOR
Super Junior has been there for fifteen years already, and they still go solid. While some members opted not to extend their contractual agreements and headed their way to build a solo professional career, others remained with regular music releases and comebacks and preferred to be active members.