In the immortal words of Stephen Covey, the genius who convinced us to micro-organize our lives into fifteen minute increments, "Effective leadership is putting first things first. Effective management is discipline, carrying it out." While he likely was referring to the austerity of self-discipline, the same principle applies to discipline of employees.
In any organization that propounds rules and policies, there will be those who break them, intentionally or not. Without disciplining those who do so, the organization is tacitly acknowledging that those, and likely other, rules and policies do not really matter. Worse, it is acknowledging that they don't matter for some people and may matter for others. The reverse, inappropriate discipline in response to a rule or policy violation is equally problematic and will likely result in depleted morale, disengagement, disloyalty and possibly claims of unlawful discrimination and disparate treatment.
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