At first thought, it can be puzzling why companies would want someone else to fix their problems (grow their business, track down inventory losses, improve technology, etc). However, there are many reasons why this choice makes sense. Here are the most common reasons to hire outside experts.
Outside Perspective - Consultants often face the same challenges in other businesses, and they can bring that experience and knowledge to focus on your issues without "reinventing the wheel."
Extra Horsepower - It can be difficult to re-assign employees to address evolving challenges, but bringing in Consultants can provide temporary, highly-skilled resources to address a wide variety of goals.
Specialized Skills - Engaging a Consulting firm allows you to access a group of professionals who provide specialized skills in areas such as quantitative research, evaluation, facilitation, strategic planning, marketing, and process improvement.
Political Avoidance - When companies face highly controversial actions (think mass layoffs), it can reduce the stress of executives to outsource the tasks to outside, 3rd-party professionals who do not face the same level of emotional impact.