Microsoft claim a milestone with their Cordana speech to text transcription service, hitting an accuracy rate of 93.1% or a failure rate of 5.9%, which is reportedly the same accuracy as you’re paying $1 or $2 a minute for right now.
No human transcriber is completely accurate. There are generally some words that are unclear, or technical terms not known to the human transcriber that need correcting in a transcript.
I’ve also been one of the beta testers on SpeedScriber, which is built around an automatic engine, and have been very impressed with the accuracy, particularly with American accents. Accuracy dropped a bit when it had to deal with my still-mostly-Australian accent.