Professor Gloria Mark ran a study to determine the impact of the constant stream of interruptions that we call work in 2019. On any given day I've got emails, phone calls, text messages, Slack messages, Zoom calls, Google Drive notifications, and Jira or Confluence notifications that can demand my attention at work.
Professor Mark determined that it takes 23:15 to get back on task after an interruption.. The study was a few years ago. It might be even worse today.
That feels pretty on-the-nose to me. A big part of my job is writing, and I can not write in 10 minute spurts. I try to block out 4-hour windows to focus on writing, but it's pretty rare that I get to focus on the writing task for 4 straight hours. There are some days where it feels like I can't get 4 consecutive minutes to focus on any specific task. So two interruptions an hour means that hour is essentially shot. I bet a lot of us think two interruptions an hour sounds pretty damn good.
Also, I don't think this study accounts for the sort of general background stress that impacts all of us. The existential dread that comes with financial or healthcare insecurity, or living in a country led by a fool that could get us into a nuclear war at any time. (If you haven't noticed, two nuclear powers in Southern Asia were shooting at each other this week.)
It's not productive, or healthy.
It also confirms something that I've long believed. People that claim to be multi-taskers are basically saying they excel at accomplishing nothing.