Suho says he felt lonely seeing his close friends debuting before him

Suho talked about his long training time on Mnet's 'EXO 90:2014'. 

In the broadcast of the show on August 22nd, Suho said he spent more than 6 years to become a member of EXO, "I become a trainee in 2005, around the time Super Junior seniors made their debut. I trained along with SHINee' Jonghyun and Taemin but they ended up debuting first". He confessed about how he felt lonely at that time as he was the only trainee that left alone. 

Upon hearing his story, Son Ho Young comforted him by saying,"That long wait is what made EXO into who they are today", Park Jun Hyung also encouraged him and said,"It's really admirable".