Takemichi is motivated to challenge the traditions and norms within the gang because he wants to create a better future for himself and those around him. He is determined to change the violent and destructive path that the gang members are on, and believes that by challenging the status quo, he can make a positive impact and prevent further harm. Takemichi's strong sense of justice and desire to protect his friends serve as driving forces behind his decision to confront the established norms within the gang.
