What containers do for you is two and only two coarse-grained things. 1. Make you more productive rolling out validated infra 2. Better utilize your hardware. B

What containers do for you is two and only two coarse-grained things. 1. Make you more productive rolling out validated infra 2. Better utilize your hardware. Both of these things imply that you were using VM/AMIs before and you were hand-crafting your entire stack using things like Chef and Ansible. If you weren't doing that before (like, if you were using Google App Engine or Elastic Beanstalk or Lambda), Docker will make you less productive than you are today.