The 19-year-old said he jumped at the chance to join Gerard Houllier's side after Montpellier did not give him an opportunity, despite him being part of the French Under-18 team that won the European Championships.
"I was nothing in Montpellier and now I am first-team player in Liverpool," said Vignal.
"When a club is relegated in Second Division and they have a junior European Champion, if they don't play him at that moment, then they will never. They even didn't want me to train with the first-team, they never believed in me."
Vignal was delighted to make his league debut in the 3-0 win at home to West Ham as he originally moved to Liverpool as a transfer for the future.
"Before signing, I met Gerard Houiller who explained to me that he wanted me at the club for the future and planned for me to join the first-team after a-year-and-a-half," Vignal added.
