The math here is pretty simple.
One hour of video takes six hours to transcribe and proof.
One hour of video takes an additional four hours to properly line break, caption and proof.
In total, one hour of video to transcribe and caption takes 10 hours.
At one dollar per video hour of captioning, the transcriptionist and captioner split six dollars per hour of work.
What quality do you expect when you are paying six dollaras per video hour to your transcriptionist and captioner?
We would suggest none.