Which was the more important cause of the failure of the League: its organisation or its membership?

In terms of organisation, the League failed because it was too Eurocentric. When the Manchuria crisis unfolded it took the Lytton Commission 12 months to reach a decision because of the distance between Europe and Manchuria. This also made them slow to act and ineffective in disputes which needed immediate resolution.The League had no united military forces which meant nations had to act on behalf of the League. Nations were therefore encouraged to act in their own interests which sparked conflict between member states. In a time of economic depression, states were unwilling to use military force or economic sanctions to enforce the League's agenda because they wanted to protect their own interests.However, the main reason why the League failed was because the USA never joined. Without the backing of the USA, the League was far less powerful than it would otherwise have been. Therefore, membership was a more important reason why the League failed.