One rule parents should live by is to never consequence kids when angry. It is easy to forget a simple rule when your kids "mess up" and get into trouble. You are mad, hurt, disappointed, and want to "make 'em pay".
Even when you feel that way, you must realize that your emotions are out of control. Situations of child abuse may often be attributed to a parent who lost their temper.
The purpose of a consequence is to remind your teens that they have misbehaved and that will not be tolerated. It is to serve as a sign to them that their parents are not going to let them engage in unacceptable behavior.
A consequence should be fair, appropriate, and useful. It should be discussed before the behavior, not afterward. If teens are aware ahead of time of what the consequence is for an infraction of the rules, they may steer clear of certain behaviors. When they know what to expect, there does not need to be a heated discussion at the time the rule is broken. It can wait until everyone is cooled off.
If you get angry and ground a child for "the rest of their natural life" as some parents have tried you are going to suffer as much as the teen. Reasonable "sentences" will make more sense once you have regained composure and gotten rid of negative feelings.