I think some people get tied up in the
connotation of the word punishment, just at they do with the word discipline. If you grew up in my generation or before it probably has a very negative underpinning for you. Punishments involved violence, either physical, verbal or passive which aimed to strip you of the pride and arrogance that led you down the garden path in the first place.
Punishments when I was a kid ranged from a smacked bottom, hand or face to such delightful things as soap in the mouth or being grounded from using the telelphone/watching TV/riding my bike, etc. for a few days to a few months at a time. Punishments were frequently overeactive, illogical, and apart from the physical ones, next to impossible to enforce. They rarely taught me anything, and usually gave me plenty of time to plot out how not to get caught the next time.
So I while I do not have any hang ups with the word punishment, I can see how some people do. I worked for a school in Costa Rica that tried to do away with punishments and create a "non-punitive" system. First it was based on a ladder of pseudo consequences (meetings, talks, letters home, all well worth whatever infraction was made), but that proved to just be a synonym for ineffectual punishments leading up to eventual expulsion. Then they worked on a system of "Restorative Justice"...as far as I could tell it was just a fancy word for punishments that were meant to make the victim/s feel better and sometimes gave the rule-breaker some ownership in their punishment. But the semantics were SO important to so many of the students and staff I didn't want to burst their bubble and tell them so. Most of the time it just lead to writing a letter, openly apologizing via e-mail to the community, lots and lots of meetings to discuss the actions and eventually expulsion.

At the end of the day discipline is just about teaching people how to improve, be it as communicators, atheltes, or members of a society. Sometimes we need to use unpleasant consequences to teach people how to improve. If my students write a crap essay, we drill essay structures and they have to re-write it. They don't like it and they see it as a punshiment, but it makes them a better writer. To me that is very similar to when my son makes a mess of the living room and I have him clean it up. He doesn't like it and he definitely sees it as a punishment, but it makes him a more responsible member of the family.
I agree with mamazee, ideally punishments should be related, respectful and (taking a stab at the third R) reasonable. BUT we are human beings and as such have an innate urge to abuse our power of authority, so if occassionally, we do not follow those 3 Rs for whatever reason, if we scream unkind things at our children, or we see them coloring on the walls and decide they can't go to the park for three months, then perhaps it is time for us to discipline ourselves, give ourselves a time out and when we are ready, apologize and try a "take two".*
I think the mistake I make most as a parent is forgetting to model for my child how to take back poor choices and make things right, which ultimately I think is the goal of
any form of discipline with regards to children, that they learn how to right the wrongs they commit.
*
Take two is something we do in our house if someone wakes up grumpy or starts being rude. We say "Let's try that again 'Benjamin needs a snack-- Take Two'"