Kakifrucht Later does not always mean better
There may be new features and bug fixes - but when running dev-master you should expect a host of problems - like potential file/database corruption, install issues, undiscovered bugs. It's possible someone accidentally wrote code that deletes everything on the system.
So ? - before running the latest developmental release - take to moment to think - Am I properly prepared to be running something that could have consequences? Because if something bad happens the correct response isn't "it broke my system help me", rather "it broke my system and here's a detailed bug report" so we can prevent it from happening to others.