One of the advantages of being human is that we are able to learn from those who came before us and not have to re-invent the wheel. I agree with those who recommend that you read about the basic rules of composition (my favorite book is Michael Freeman's The Photographer's Eye). I also recommend looking at gobs of images by other photographers. Feel free to break the rules but, in that case, don't be surprised if your images are not pleasing to others. There is a lot of human psychology behind the development of those "rules". As ANDS! suggested, there is a lot of personal opinion involved, but it is still important to understand the basics.
Along these lines.....
Composition has been discussed and examined for a couple of thousand years now. Not just in photography but in all the visual arts. Over time, it became clear certain compositional elements/techniques are more pleasing/stronger/more compelling to the eye than others.
Centered compositions tend to be some of the weakest/least compelling.
When you watch TV or a movie, be aware of the composition the camera operators use. Little of it is centered and use of the ROT abound.
Rules is not a good name, guidelines is a better term.
Diagonals, leading lines, verticals, horizontals, all have their part in making a pleasing composition.
If you want to portray dignity and strength, your image will be stronger if it has a strong vertical lines.
If you wish to convey speed, compose using diagonals.
If you want tranquility and peacefullness use horizontals.
You might want an image to convey several feelings like speed and strength together, so you may want to mix some of several compositional guides in a single image.