As the hiring manager, you have identified the need to make changes in the organization. There's growth and there are changes needed to keep up with the market trends and competitors. The company has always promoted from an internal pool of performers. As the hiring manager you know there are employees who are solid with the current technical knowledge of the business, however, no one really has the innovative and competitive knowledge to move the organization to the next level. What do you do? Do you stay loyal to the 'promote from within' philosophy and risk the organization's progress and growth? Do you risk employees becoming disengaged because they feel betrayed by the hiring of externals?
The answer may lay in several points to consider. First, what are you trying to achieve? Do you have the internal resources to achieve your goals and strategies? Perhaps you can consider a combination of changes that will strengthen the organization that include both internal changes, internal promotions and external hires. However, you should never be concerned with making the right decision for the business. If that means hiring externally, that's what you do. As a part of the decision to hire externally, insure a communications plan is in place to assist employees in understanding the business strategy for the decision.
Going forward, talent planning to include succession management will assist in managing the potential talent gaps and will assist in updating the philosophy of 'only promote within'.