Each brace is a precise handle on the tooth. Braces are the best way to move teeth because teeth are round and slippery - hard to move unless you have a good handle on them. Retainers and aligners cannot move teeth as well as braces because they don't have the same precise handles.
You can't just place the handle anywhere on the tooth. Well you can actually, but it will take much longer to straighten the teeth and it will take more work for the orthodontist and the patient. The better the braces are placed on the teeth, the better and faster the teeth will move.
I place all the braces in my office - attention to detail. And I position the braces differently for different patients because teeth have to move differently. If you compare two people, one may have the upper braces close to the gum. The other may have the braces farther from the gum. I will even sometimes place a brace flipped or upside down. This is hardly noticeable when you look at it, but it can make a big difference in moving the tooth faster and more comfortably . Not everyone's braces are placed in the same position because people's teeth are different.
I want to get your teeth straight and your braces off, as quickly and as comfortably as possible. Attention to detail in brace position is a big part of that. And that is why all the braces in my office are placed by me.