Despite being one of the main European powers, early 20th C. Russia was economically and industrially behind other European powers by a serious margin. Additionally, still recent were the military embarrassments of the Russo-Japanese War, and the effects of the 1905 Revolution that followed. People like Lenin and the Bolsheviks actually desired German victory in WW1 because Germany was so much more advanced (Source: Young Stalin - Simon Sebag Montefiore). The severe lack of Russian national unity of course manifests in the successful 1917 revolution, but the cracks were clearly present before WW1. Essentially, you can't expect to do well in a global war when you're already on the verge of losing the war at home.