Favouritism often implies someone has an unfair advantage because of personal connections. He got promoted quickly due to favouritism, and not his skills.
Pro Tip 2/3
Negative Impact
Favouritism in teams can lead to resentment and reduce cooperation among members. Team morale dropped due to the manager's obvious favouritism.
Pro Tip 3/3
Cultural Sensitivity
Perceptions of favouritism can vary widely between cultures, affecting how it's seen and handled. She didn't understand the local customs and was unwittingly showing favouritism.