Docker allows the platform to move faster.
Here is how Adrian Cockcroft (former CTO Netflix) sees it (http://www.slideshare.net/adriancockcroft/dockerco... )
From the business perspective, an important performance indicator of an application delivery platform is the ‘feature velocity’ that it allows. This relates to the time elapsed between the moment that a feature (or feature change) is requested, and when it can actually be tested out in the business.
Docker has a number of features that help increase that feature velocity.
The overall picture and feature set will be touched upon in the following section.