The reason why 'Youth' didn't invite any big name actors was mainly because it was a youth movie, and youth movies usually didn't need too many luxury lineups and top actors. In addition, the director and scriptwriter team of the film were also the main production team. They had enough experience and ability to control the entire filming and production of the film. Finally, the budget of the movie was relatively low, so there was no need to spend a lot of time and money to hire top actors.