With the Articles of Confederation, the federal government had little to no power and was very weak. The government could not do a lot of crucial tasks, one of them being they could not pass any laws without nine out of thirteen of the state's approval.
Since it was very difficult to pass new laws, not many were being created or passed during this time. It was very rare that many of the states agreed on one thing and many during this time were very defiant of the government and wanted to do things by themselves.
The Northwest Ordinance was where new territories were created Northwest, where there were new policies and land. Many people decided to move Northwest after this, as they saw it as an opportunity for agriculture and other purposes.
The provision that was included in the Northwest Ordinance that was exceptionally important was the banning of slavery within the Northwest territories. All of the new states in the Northwest outlawed slavery. This was important as it was very hard to pass these types of things under the Articles of Confederation.