Yeah, I realized I didn't really give any context for that statement. It's important for reviewing the quality of your audio before you decide to upload it, or re-record. Many, if not most learners will be listening to your course through headphones or earbuds. Things like background noise and breath noise can be much more noticeable in headphones than they are through speakers, so you might unknowingly be uploading videos with distracting audio issues otherwise.
So, it's a good idea to use headphones or decent earbuds while editing your videos, so issues like that will stick out to you.
The standard pro headphones are the Sony MDR-7506, but it doesn't really have to be anything fancy.
