Nothing is wrong? There are times when your officer just has a crappy load out of missions, combined with a few bad sectors and it seems like there isn't enough Marauding going around. It happens now and then.
1) Don't just rely on the disable missions. There are other uncommon missions that have an 8 hour processing time. They have many names but I think one goes like "Initiate raid against <insert race here> colony. They too give prisoners, contraband, and other goodies.
2) All raid/disable missions are based on a randomizer. Some days you'll hit it and others you won't.