Commentaries are often discussing the ineffectiveness of competition authorities or antitrust agencies. Yet, these commentaries often ignore the legal structure behind competition or antitrust laws. In general, these laws can be enforced via the courts in which the authorities or agencies become the plaintiffs and the firms are the defendants. The plaintiffs must then prove their case to a judge. That is, we have litigation.
In contrast, the plaintiff and the judge are essentially one party under regulation: a regulatory body. While one can argue that there may be internal debates within a regulatory body, these debates are likely to be less transparent than in a court.
Consider what happens if the police, the prosecutor, and the judge are the same body versus if they are different bodies. One consequence is that a single body may find it easier to enforce the law in question. However, there are reasons why lawmakers may want different bodies to enforce their enacted laws despite the additional difficulties. These reasons may then be open to discussion.