How did factory workers's lives compare to slaves' lives?

I'm not sure one could really make a comparison. Granted some factories had horrid working conditions and very low pay. still the workers went to their own homes at night and could seek other employment. Not so for slaves. They worked incredibally hard , most for no pay whatever and could be bought and sold on a whim by slave owners. Many families were literally torn apart by slave auctions. They were also beaten by over seers for minor infractions.