What were the shortcomings of the Versailles system? What were its merits?

Disadvantages:

Exclusively the interests of the countries that won the war of 1914-1918 were considered. While the countries that suffered defeat, as well as in the early stages of Soviet Russia, were subjected to discrimination and significant restrictions. Peace conditions for them were unreasonably difficult and burdensome. All this will eventually lead to WWII.

Advantages:

For the first time, the idea of ​​collective security arose. As a result, the League of Nations was formed (however, the organization proved to be extremely ineffective, so this can be considered a virtue conditionally). The process of globalization of international cooperation has begun.