The Articles of Confederation withheld many powers of governance from the federal government, causing it to be simply too weak. For example, the federal government could not collect taxes, which is necessary to governance. The federal government could not properly enforce laws, since any states could decide to ignore a law it didn't like. It didn't even have judicial power as the Courts weren't invented under the Articles of Confederation.
It created a federal government that was too weak to even govern.
Hope that helped.