Why did plantation owners MOST prefer to use slaves over indentured servants?

There were two reasons why they turned to slavery. The first one is indentured servitude was a contract for 7 years and often people didn't finish out their contract once they arrived. This meant that they could fade into the population of colonists and no one would know they were indentured servants. While slaves were African American and anyone who was black was a slave no matter where they were. This is the second reason why slaves became popular because no matter where they were they could be picked out as a slave. To leave a plantation they had to have a pass, and slaves were property while indentured servants were workers.