A marathon runner can't have the pace of a 100m sprinter but software engineers are expected to maintain sprint pace for perpetuity.
And give detailed status reports Every.Single.Day. So there's no possibility of a breather, ever.
This is not at all what it used to be like pre-agile. There was time to think deeply about solutions. It was ok to slack off a day (or three) and make it up later when you got into The Zone.