I've learned to get any deep focus, I need to eliminate emails and Slack for this time (including things by the closest collaborators, directly on the project,

I've learned to get any deep focus, I need to eliminate emails and Slack for this time (including things by the closest collaborators, directly on the project, life partners, anyone). There are exceptions and emergencies (then, and only then - unscheduled phone calls), but only in case when it is worth canceling all daily progress.