Hello~
They most likely wanted slaves to be afraid so they did not collect the courage to escape or disobey. With low self esteem they might not try anything.
Good luck!
Ary~
OK so basically Faulty coordination<span> is joining two clauses in such a way that the meaning is illogical</span>
Move/slide/crawl/creep/slither/wriggle/squirm/edge/sneak