Traore joined the Blues from Auxerre in 2013, but played just 16 times for the club, spending two seasons on loan at Vitesse and Ajax.
Now, having joined Lyon for a fee of £8.8 million, Traore claims that last season confirmed his decision to leave Stamford Bridge, having been denied the opportunities he felt he deserved.
"It was time. Considering my age and for my development, it was time for me to leave the club,” he is quoted as saying by the London Evening Standard .
"I could have stayed at Chelsea and played a few minutes in every game, fighting every day for a spot, knowing that I'll never get a spot, I trained at the club, I did everything.
"Two seasons ago, I challenged the starters but we all know what happened last year. I was there during pre-season and then I was sent out on loan.
"So this year, I did not want to re-live the same scenario. It was time for me to find a stable club where I could play first-team football, where I could be one of the key players in the team.
"To be one of the key players in the team, you need to fight, and here, I'll do everything to be amongst them, and I'll give everything for the club."
Chelsea's infamous for struggling to integrate its huge number of youngsters into its first team, with very few players having broken through in the last decade.
The likes of Kevin De Bruyne and Romelu Lukaku both arrived for huge fees but found their fortune away from the club after failing to break into the starting XI on a regular basis.
However, there's an even greater number that have risen through the youth ranks only to leave on loan most seasons and played very few competitive games in a Blues shirt.
Antonio Conte's side loaned out 38 players in 2016-17 and a similar figure is expected this season.