Criticism as an evaluative or corrective exercise that may take many different forms. How exactly people go about criticizing, can vary a great deal. In specific areas of human endeavor, the form of criticism can be highly specialized and technical; it often requires professional knowledge to understand the criticism.
To criticize does not necessarily imply "to find fault," though it is often considered this way. Often it involves active disagreement, but it may only be someone "taking sides," exploring the different sides of an issue or providing critical thinking.
Fraud in the martial arts
In case you haven’t noticed, I don’t like frauds. I have been in and around the martial arts for over 50 years and, although I don’t know everything about them, I know enough to recognize frauds. When you know what to look for, you too can recognize martial arts frauds. I consider my life’s calling to inform current and potential martial arts students about how to recognize fraud when they see it.
Some think that before you may criticize them, you must pay them. If I want to learn your martial art, I have no problem paying you to teach me. However, why should I have to sign up for your martial art class or buy your book, video, seminar, etc. and make you richer before I may criticize your philosophies, concepts, beliefs, or martial art. If I learn about your philosophies, concepts, beliefs, or martial art from other sources, such as the library, publications, or Internet, why do I need to pay you before I may comment on them? No “master” or “organization” seems to mind if you praise them without paying them; however, if you criticize them, these same people think you should pay them first.
You don't know me
Martial art “masters” and “organizations” sell books, videos, and home study courses that they say will permit you to learn and perfect all their special techniques, and many will award you rank without ever meeting you. They think a person may learn their art from a book, video, or home study course. However, when someone criticizes “masters” or “organizations,” their defense is that you have to meet them in person or experience one of their classes in person before you may know enough about them to criticize them. Well! Which is it? If I may pay you and learn your art from a book, video, or home study course without ever seeing you or taking one of your live classes, then why is it that I cannot criticize your information without ever meeting you or attending one of your classes?
You haven't experienced it
Some say you cannot criticize or even comment on a "master" or a martial art unless you have trained in that art with that master. The premise is that, after training with the master, your perceptions of the master and the art will change and that you too will believe what they are teaching. Not everyone falls under the spell of charismatic "masters." That is why most of them have so few followers. I have not experienced using heroin, but I know enough about it to know it is harmful not only to the user but also to the public. Using my intellect, training, education, and common sense, I can certainly criticize heroin users and warn the public of its use without ever using it myself. I am not foolish enough to spend my time and money to "experience" the teaching of a pseudo-master, motivational guru, or any other fraud.