One might think that a Delegation of Authority letter repeats to a large degree points that a well-worded job description should be covering. In reality, a job description is a very poor substitute for an effective Delegation of Authority. There is a very simple explanation for this.
1. Job descriptions are often non-existent, vague or not regularly updated
Good job descriptions are a rare animal in many organisations. Even if they exist, it is a fact of employment life that job descriptions do not follow role evolution quickly enough, or do not cover all decision making aspects of that role.
2. Job descriptions are not comprehensively aligned with existing processes leaving gaps and confusion in what a job holder can do transversally
Processes in many organisations evolve, get adjusted and abandoned very quickly. HR teams simply have no visibility into what is going on where operations-wise, and even if they do, have limited resources to keep adjusting job descriptions in real time. This is why, even if job descriptions cover well vertical responsibilities, they are hopeless when horizontal interactions are concerned.
3. Job descriptions are deemed confidential and not internally disseminated
This last point could be the first. In many instances, job descriptions are not widely communicated to all in the organisation, as Delegation of Authority best practice for Good Governance suggests. This is because job descriptions are often seen as part of personal employment contract and therefore any change in scope or limit of delegated authority could have bearing on individual employee terms and conditions.
By contrast, a Delegation of Authority framework is part of the organisational rules and policies and therefore any change in authority scope or limit for the role is separate from employment relationship with any particular individual.