Probably the most fundamental weakness of the Articles of Confederation, and the most basic cause of their eventual replacement by the Constitution, was the

Well from what I know the articles of confederation ended up being replaced by our fundimental constitution because the articles gave too much power to the states and not enough power to the central government as back than we were worried about becoming Britain from which we just separated so we didn’t want to make the central government too powerful (which is why the states were given more power)