I believe recognition is the key to employee motivation and job satisfaction. Salary, benefits, flexible work hours, and other criteria are important, but it is recognition that is the source of job fulfillment.
I learned this by watching my father run our family business. He was someone that never seemed to be in a hurry and always wanted to hear what you had to say. That included all our company employees and as I was to learn later hundreds of others as well. The result of his people first management style was employees that stayed dedicated to our company providing the kind of service few could match. They liked working with him. Why, because they knew that what they did mattered. They understood the role they played and how their performance affected everybody else.
Leaders would do well to put systems in place to facilitate employee feedback both good and bad. The goal is to let each person know how they are doing and that what they do is appreciated.