There are several reasons why Europe wants Erdogan to lose.
Erdogan's authoritarian authority is becoming more entrenched. Turkey has grown increasingly dictatorial under Erdogan. He has suppressed criticism, imprisoned journalists, and extended his own authority. Many people in Europe are concerned about this, seeing it as a danger to democracy and human rights.
Foreign policy under Erdogan. In recent years, Erdogan has also embraced a more muscular foreign policy. He has fought with the EU on migration and has backed Islamist parties in the Middle East. Many Europeans are concerned that Erdogan would destabilize the area as a result of this.
Erdogan's fiscal policy. Erdogan's economic policies have also been widely condemned in Europe. He has adopted a program of excessive borrowing and spending, resulting in high inflation and a weak currency. As a result, Turkey has become a less appealing investment location, and it has also contributed to the country's present economic problems.
Europe wants Erdogan to lose for all of these reasons. They expect that a new Turkish administration would be more democratic, respectful of human rights, and helpful with the EU.