Limits without love are ineffective. Successful parents know that teens need a balance of love and limits. Successful parents know how crucial it is to really listen to their children. When we listen to our teen's point of view, they're more likely to feel that we're on their side. Then, they will be more willing to listen to what we have to say.
Nothing shuts a kid up faster than criticizing their beliefs and opinions too quickly or harshly.
That helps a teen see his parents' perspective while keeping communications open. So keep both your expectations and standards high. But successful parents are also realistic. They know their teens won't always meet their expectations. So they give teens plenty of positive input.