Sprints can start/finish with quality related work - improving logging, architecture, cleanups, whatever needs improvement etc. It should be embedded into the

Sprints can start/finish with quality related work - improving logging, architecture, cleanups, whatever needs improvement etc. It should be embedded into the process so it happens all the time. This should give a feeling of sustainability. To put it in other words, you should not feel at the end of the project you need this kind of time because you were doing it all along. There should be no feeling of exhaustion and relief at the end of the project. That's a sign of non-sustainable process, people burn out on it, employers loose more money at the end and people feel like shit - not great, better for everyone to avoid.