This is one of the costly mistakes that most of the business owners do make and it may create a lot of jealousy amongst workers, which way may not be so good and healthy because it could be disastrous sometimes.I believe not revealing salaries scale to everybody is the start of professional jealousy , the salary scale must be made known and be opened , but you need to explain why some staffs are getting much more than the other , maybe because they have been working before they came (years of service) , or because of the certificates , and many more .
But if you like some staffs , you don't have to show it sonthat others will know , that alone can start a professional jealousy.