It isn't just machines that have trouble
You don't need 100% accuracy, but you need 100% accuracy in the right places. My iPhone does voicemail to text, and even though it isn't always 100% I generally don't have to listen to the message because a 95% accurate (or whatever) transcription is good enough.
For meeting notes you'd want near perfect accuracy, especially if you want it searchable. If I'm looking for the meeting where we discussed the outcome of "project athena", but its name was transcribed as "project tina" in a meeting we were informed it was canceled then I'm not going to be able to get that critical information via search. Whereas if I was reading the meeting notes or received notice of the cancellation via voicemail I could easily infer what "project tina" really was.