In what ways could the failure the enforce conscription weaken rome?

"Their conscription were a failure due to not enforcing to everyone. As such there was not many people to choose from. It weaken Rome because armies need manpower to hold the front since equipment is useless if there is no person to use it. It also didn't enforce it on mostly on the useless people like the rich who don't contribute very much to society and the cooks and bakers who can't cook if all the farmers were conscripted  which would mean no food. This weaken Rome more than it benefited her."