Growth (there are 2 sides to it)
Growth can give a competitive advantage in size, ie economies of scale like improved purchasing power owing to size, significant savings from centralised services, greater opportunity for staff development, etc.
On the other hand, there are some dis-economies of management, such as increased organisational layers with management more divorced from customer and staff that can restrict communications and organisational flexibility, increased chance of silos developing within the organisation.
As an organisation grows, it tends to become more bureaucratic and process-control orientated.