In weightlifting, form and technique are everything. You can think you’re doing everything right, but you wouldn’t know for sure unless you’ve been trained by a professional, actually watched yourself lift, or ideally, both. Sure, you can ogle yourself in the mirror, but a better way to learn is to record a video of yourself with your phone’s camera. Then you can review it later (ideally with a trainer) and see what you should fix.
The other day I was talking with a high level coach about exactly this. She originally didn’t like “distance training/coaching”, but then that was before the days of the internet. As the article mentions, pretty much everyone has a cell phone these days that includes the ability to take pictures and video. Add to that VOIP tech like FaceTime and Skype, where we can video chat.
Also mentioned in the article is the bit about being self conscious. It reminded me of the time I started training martial arts in front of a mirror. Once I got over not liking seeing myself, it became a great tool.