These things are tools to be used. If you use focus on the tool and not the end user, things will go badly. Typically you will see teams that are very hyper focused on some particular metric (time, points, stories churned, etc). Yet not focusing on 'how do I get my customer what they need'. These tools help devs break down the tasks and tell the end users 'hey we only have this amount of time so focus!' If they become about metrics or just randomly skip steps that depend on each other, you will fail.