There are a lot of factors that go into making someone a “favorite” player. It can be their onfield prowess: perhaps they’re the best batter or pitcher you’ve ever seen in action, or they make such mind-boggling defensive plays you know it will be Must See TV to tune in whenever they take the field.
Perhaps they’re just charming and funny and have developed a dugout routine that makes you chuckle, and their gift for a good interview never fails to bring a smile to your face, so you find yourself cheering for them as a person instead of as just a player on the field.