When declaring the performance of a product model, the manufacturer can deliberately choose to declare a value corresponding to the worse performance possible for that product model, while also being possible that actual units on the market (of that product model) have a better performance, e.g. because they have higher quality components.
Disclaimer: Please note that the European Commission cannot provide a legally binding interpretation of the EU legislation, as this is the sole competence of the European Court of Justice. Any remarks from the European Commission services are without prejudice to the position the Commission might take should related cases arise in a procedure before the Court of Justice.