I think that one problem for me was that people didn't often tell me WHY; they mostly told me WHAT. You have to iron your shirt because it's a rule. You have to be home by 10 because that's curfew (actually my parents believed in curfew as defined by the event, which I appreciated then and still do). You can't eat that because it's bad for you. This kind of logic is fine for kids, but it starts to backfire with teens. And ESPECIALLY if they've found out that some of the things that they were presented as absolutes are only true some of the time, if at all... well, everything else you say becomes doubtful.
For example, if you say "You have to study or you won't get a good grade", then boy are you undermined when no study or poor study correlates with a good grade anyway. Talking to teenagers successfully involves so much conditional framing, and this at a time when they're some of them taller than you and twice as stubborn, and there you are with your wishywashy it might could... well, it doesn't feel nice.
I have noticed, though, that very specific directions with justifications tends to get things done better, repeatedly, than "because I'm the parent, DAMMIT" does. Even if that's what I very much want to say. I think it also helps to really encourage a teenager to question why every single time it isn't volunteered if they don't know. And (and I actually very much enjoy this part of parenting) it is very useful to have teens suggest and justify different ways of doing things, first because it encourages them to think through their alternate idea before they try making soup by dropping in whole potatoes and trying to cut them up later, and second because they may have a better way of doing things, since that is (after all) what their brains are supposed to be doing now, so it benefits everybody. Plus it's good practice for people to question what they don't understand and be answered politely as a matter of course, as it makes the world a more pleasant place to live when people are in the habit of not viewing questions as challenges, but as opportunities to explain.
Just a thing I've been thinking about for the last week or so. Writing it down to help myself remember.