Shift-Left Operations in the Cloud versus the Datacenter

Do you run or walk? When you do, is it on a treadmill or in the street? And why does this have anything to do with cloud and datacenter operations? Surprisingly, they have more in common than might be thought. So I am asking for a few paragraphs of leeway here. Lets start with running on a treadmill. In this scenario, you can control the lighting and climate. You will never hit rain, or have an obsticle or another runner in your path.