Why is it important in leadership not to play favorites?

Thanks for invitation,

Following our colleagues' replies.

because the other employees may get offended in which may resolve in a conflict inside the workplace, and employees will start taking sides instead of working as a unit

Leaders lead by example, and Managers play favourites

Leadership is a "Trait" and Manager is a "Title"

In any organization, it is important to reward high-performing employees in order to motivate and retain your talent. Without this structure, favoritism can begin to take root in the workplace, which negatively impacts a company’s culture and its bottom line.

Hi Optimize the success points for specific goals

Thanks

I support my colleagues answers

Leaders often fall into the trap of favoritism when they overlook or excuse lesser quality of work or spend personal time with select employees, while excluding others. Although these may seem like small issues from the perspective of the manager, they are not viewed that way by employees. A leader must adhere to a transparent framework that managers practice and employees understand. 

Blatant favoritism of one star employee can lower the morale of all other employees, as other good employees will likely be aware that their peer is enjoying extra perks while their own hard work goes unnoticed and unrewarded. As a result, these performers might feel neglected and unmotivated. If employees sense a culture of favoritism, this may discourage professional development. 

To avoid playing favorites, it is essential to ensure that rewards for employees are tied to performance. One way to avoid this is to establish a set base salary for all employees of a certain position. Anything more should be given out of merit on a case-by-case basis and the same standards should be set for all. 

Overall, being aware of the pitfalls of favoritism and developing a strategy to fairly reward strong employees can ensure the retention of these employees, while keeping motivation and office morale high.

Leader has to keep an eye on each & everything. Leaders are those who have to feel the problems of all & have to rectify those. Therefore, a leader has to be neutral to all. Hence cannot play favorite to anyone.  In case he/she plays,then he/she cannot be a good leader.