One piece is a very enjoyable adventure story with some really good characters and cool fights. Most people like one piece mainly because of this and because it has been good since it started. It never leaves you bored or disappointed. Even only for this it is good enough to call it one of the best anime of all time. But if you are looking for more than just that, if you need something more, i am sure you will find even more than you would expect. I am not saying that meaning is only good thing in things and thing can't be good if they don't have meaning in them, i believe art can have 0 meaning and still be amazing or can be ugly but have so much meaning that it still makes great art. I think One Piece is in perfect balance of how it looks and what meanings it has behind those looks. It kinda reminds me of The Matrix with that (great action movie and great meaning and philosophy behind it).
I also want to write about main complains people have against One Piece. First would be animation. When i started watching One Piece i didn't like animation either, but than i got used to it. Not only that animation got much better after years and now i actually like it. I think the type of animation One Piece has may not be the best but its use to showcase character emotions is perfectly used (feeling can be exaggerated but it makes you feel it which is great use of animation in my opinion). Second main complaint people have would be that it is too long. It is too long but as I said before One piece will not make you feel bored. There are not much fillers in One Piece and when there are they are pretty enjoyable too. The last complaint would be that its story is repetitive. Most people who say that have watched like first few arcs when they were kids and they think that all there is to it is: they go to an island, fight, win, repeat. Well i understand why they say that but that's not really true if you watch it you will understand its not. Also people say it has too simple goal, Main hero wants to find the great treasure One Piece and become pirate king. It's not that much simple, in reality he doesn't really care about treasure or becoming a king, in his mind pirate king is a man who is most free, who can do anything he wants and that's his goal to be the most free person in the world. People who have a feeling in their life that people are trying to pull you down, trying to close your mind, trying to make you the same way they are will understand how much that means and that it is much more than just a treasure or a name of a king.
The story of One Piece may be the best part of it. IT's long but not really drawn out. Eiichiro Oda created a whole world to explore together with great characters. And there are some things Oda obviously planed and wrote years before we saw it on anime and when we did it left mind-blown. And there are more thing waiting to be revealed in future too. It's a story about everything. Story about birth, death, being a parent, about brotherhood, about sacrifice, about loss, about friendship, about war, about peace, about freedom, about dreams, about life and existence itself and SO MUCH MORE there is no way you can count a all of it down. And it never get too annoying with one thing. It never gives you too much of anything that can make you bored. The story writing is so good that some 1 episode flashbacks can be as good and even better than whole great movies. For example one of flashback stories really reminded me of a great movie Life is beautiful and i even felt like this was better written.
One piece changes your life. It changes you but it never gives you straight teaching how you should be or not be. There are just so many kinds of great characters and they just do their things and you relate to it. It never is like marines are good and pirates are bad, or pirates are good and marines are bad, there are good and bad people on both sides. Yes our main heroes are pirates but they never say pirates are all good, we see some pirates killing innocent people and marines who don't care about people. Characters never stand there and say something like: "oh i am a good person and you should be too". What you learn from One Piece comes itself. You watch characters, they go through something, that changes them and One Piece makes you feel like you are going through the same thing with them and it comes to you more like experience than as a lesson. You feel it and you get it. It never tells you what is right and what is wrong or what is good and what is bad. One Piece just makes you feel what characters feels and after that its up to you, its your own decision if you want to or what you will learn something from that feeling.
In conclusion i would like to say that One Piece is not one of the best anime but also one of the best masterpieces of art ever created (and it's not even near finishing yet and i can already say so). One Piece won't make you disappointed. It may not mean as much to most of the other people out there but i can assure you at least this much that it will be enjoyable to watch for everyone.
P.S. Don't watch English dub.
