Two possible definitions of "Execution" from the FreeDictionary.com:

1.  The manner, style, or result of performance
2.  The act or an instance of putting to death or being put to death as a lawful penalty.

Its weird how the two wildly different definitions landed on the same word isn't it?  But in today's fast-paced, delivery-oriented business climate, the two definitions are logical partners.  Execute...or be executed.

Innovation cannot happen without some kind of execution.  Remember, ideas aren't real until they are "executed."  That's why every definition of innovation contains an action of some sort.  An action that, as noted above, results in the manner, style or result of performance.

Most organizations do not suffer from a shortage of ideas.  Employees, management, vendors, partners and customers all have ideas on how to make your product/service better, faster and cheaper.  But again, ideas are the easy part...they mostly just happen.  Step two takes action or execution.

Figuring out what problems you want to solve...takes execution
Collecting ideas from employees, management, vendors, partners and customers...takes execution
Filtering ideas and deciding which ideas you want to commercialize...takes execution
Committing resources, both financial and human, toward commercialization...takes execution
Developing a solid project plan to move the idea to reality...takes execution
Marketing the product/service and making the idea known to the world...takes execution
Making a profit on an idea...takes execution

To be a good innovator, you need to excel at execution.  There is no other way.