They are appointed by the elected(the governments of the countries and the European Parliament, which are all elected).
When you say it like "they are not elected but appointed", you make it sound like some 3rd party is appointing them and you have no power on it but those who appoint the members of EC are the members of EP(elected every 5 years) and the national governments(elected accordingly to the local laws).
If you you want to make it sound undemocratic, you can say that the US president is elected by the electoral college and citizens of the USA have no way to vote for their president.
When you say it like "they are not elected but appointed", you make it sound like some 3rd party is appointing them and you have no power on it but those who appoint the members of EC are the members of EP(elected every 5 years) and the national governments(elected accordingly to the local laws).
If you you want to make it sound undemocratic, you can say that the US president is elected by the electoral college and citizens of the USA have no way to vote for their president.