As a teen and family therapist the most common issue parents bring into the room is that their teenager is defiant, disrespectful, talks back, and yells. When I ask about parenting and discipline in the home it is rare that a parent includes in the description that they themselves yell. Once I dig a little bit, more often than not I find that the parents yell or they do that yelling whisper thing that they say technically isn’t yelling.
Raising children can be frustrating and sometimes can feel totally hopeless. Often parents automatic tendency is to revert to yelling and repeated lecturing when their child does the wrong thing. I would be all for it if yelling worked. There are a few instances when yelling and obsessive lecturing scares the child into temporary compliance. I believe that these moments reinforce parents believing that if they find the perfect lecture given with enough anger and loudness they will eventually get that compliant child that they are praying for. Unfortunately, the only type of child for which yelling works is the compliant tempered child. The problem with this is that these children are more likely to be traumatized and would have listened no matter how you delivered the message.
Your children, especially teens, are being affected by your yelling and not in a good way. Some of them are building resentments, some are learning to yell and be angry in conflict, some are being traumatized and broken down, and some are getting the message that they might as well give up and remain defiant. What is not happening is long term change or healthy relationship building.
It is your job as parents to eliminate yelling and obsessive lecturing from the home as a whole. Even when you feel desperate and like nothing is working, reverting to yelling is far too damaging in the long run. If you are a yeller you are responsible for finding a way to change before you worry about any other parenting goals.