The answer to this question is provided by the European Commission.

As a matter of principle, the publication of competent authorities’ decisions is an act of transparency and accountability towards their market participants and to consumers/investors. Article 54 should not be read as limiting the power of competent authorities to only publishing decisions on penalties. Competent authorities in any case are administrative bodies, and may be subject to national administrative law (in addition to the Union acquis) which may allow for the publication of all their decisions.

Disclaimer provided by the European Commission:

The answers clarify provisions already contained in the applicable legislation. They do not extend in any way the rights and obligations deriving from such legislation nor do they introduce any additional requirements for the concerned operators and competent authorities. The answers are merely intended to assist natural or legal persons, including competent authorities and Union institutions and bodies in clarifying the application or implementation of the relevant legal provisions. Only the Court of Justice of the European Union is competent to authoritatively interpret Union law. The views expressed in the internal Commission Decision cannot prejudge the position that the European Commission might take before the Union and national courts.