Outsourcing

You can maintain focus for your team.

Perhaps you have an old application which you need to re-engineer to fit into your modern Intranet. Your developers are excellent with the new technology, but no one who knows the old technology is still with your firm. Sure, one of them could figure it out -- but they aren't interested in doing it, it would add time to the project, and the skill will never be used again -- so there's no value for you as a manager either.

Outsourcing this project with a good firm gets you where you need to be, while keeping your own resources focused where you want them to be, and where they want to be.