The United States Government could not tax the states and therefore had no money, they could not control trade between states and states started putting tariffs and taxes on other states goods. They were treated as a United States. Not one Country. Most importantly, shown in Shay's Rebellion, they couldn't raise an army. Only ask for volunteers
The confederacy passed the conscription act because the army needed more people to serve in the army as the number of volunteers declines and the number of casualties increased.
Explanation
At the beginning of the civil war,both the confederate states and the union army did not use conscription but in the later years the war took a violent turn.People hesitated to join the army and the number of soldiers in the confederate army decreased visibly.
In order to avoid defeat in the war, the confederate army wanted more men to join it and they enacted the act of conscription which made it necessary for all white men between the age of 18 and 35 to serve in the confederate army if called.