Definition

A feature is a work product that fulfills one more more stakeholder needs. Lead time, also known as end-to-end cycle time, for a Feature is the average time from when a Feature is first created to the time it is delivered.

Once the Feature is created, it goes through approval and becomes implemented:

1. New: Stakeholder sees a business need and submits a request to have that need fulfilled. This is the start date of the lead time.  
2. Exploring: The organization takes the request from the business release queue.
3. Defined: Detailed requirements and estimates have been gathered.
4. Planned: The development teams approve the feature's requirements.
5. Accepted:  All teams that need to do work related to the feature have agreed to implement the feature in the current release.   
6. Implementing: Developers and testers work on validating results and testing begins.
7. Ready for Delivery: The first attempt to deliver the feature. 
8. Delivered: All application versions of the feature are delivered into production.  This is the end date of the lead time.

The overall lead time can be calculated by finding the difference betwen the start date and end date.

Feature Lead Time = End Date - Start Date

The Feature Lead Time is the total of the process times, during which the feature is implemented bringing it closer to being delivered, and the queue times, during which a feature could be waiting in a queue, between the start and end dates. Queues can inadvertently increase the lead time. 

Lead time can be measured in seconds, minutes, hours, or days.

Conclusion

Because the lead time is not measured until a feature is ready to be delivered, it may be a slow indicator of performance.  If you would like more frequent releases with business requests moving quickly through the lifecycle, adopting lean practices in order to detect bottlenecks and inefficiencies can provide opportunities for improving the lead time. Controlling the queue (or batch) size is one lean approach to consider (see DevOps Principles).