Single-Task Focus
Multitasking is a myth. What feels like doing two things at once is actually rapid task-switching—and it’s destroying your productivity.
Stanford research found that heavy multitaskers performed worse on attention, memory, and task-switching tests (Ophir et al., 2009). The people who multitask most are worst at it.
The Cost of Switching
Every task switch has a cost:
- Attention residue: Part of your mind stays on the previous task for 10-25 minutes
- Ramp-up time: Getting back into flow takes additional minutes
- Error rate: Increases with each switch
- Mental fatigue: Switching is exhausting
The math: Check email 20 times/day × 10 minutes of attention residue = 3+ hours of impaired focus.
Deep Work vs. Shallow Work
| Type | Examples | Approach |
|---|---|---|
| Deep | Writing, coding, analysis, strategy | Single-task. 60-90 minute blocks. Zero interruptions. |
| Shallow | Email, Slack, admin, scheduling | Batch. 2-3 blocks per day. Process quickly. |
The mistake is mixing them. Email during deep work ruins the deep work. Don’t.
The Protocol
For deep work:
- Close all unrelated tabs and apps
- Phone on Do Not Disturb, face down or in another room
- Set a timer (25-90 minutes based on task)
- One task only. Complete or time-box before switching.
- If a thought distracts, write it down and return to task
For shallow work:
- Batch into 2-3 dedicated blocks
- Process quickly (2-minute rule: if it takes <2 min, do it now)
- Exit when block ends
Set expectations: Tell colleagues you check email at 10am, 2pm, and 5pm. They’ll adapt.
Success Metrics
- Hours of uninterrupted deep work per day (target: 2-4)
- “Flow state” experiences per week
- Time to complete typical tasks (should decrease)
- Error/rework rate (should decrease)
The person who does one thing for 4 hours beats the person who does four things for 1 hour each. Protect your focus.