The weakness of the articles of confederation was that it created a weak central government.
In theory, this should have been fine. The States had a long history of tending to their own problems.
But the central government had no power to levy taxes and this was a big problem for a newly formed country that had just taken out massive debts to fight a war against the United Kingdom.
And so, the government formed by the Articles of Confederation was destined to fail as it was not strong enough to bring together the colonies and was not allowed to raise taxes.