Single-Task Focus
Definition
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.
When This Applies
- You feel busy all day but accomplish nothing meaningful
- You’re constantly interrupted and can’t sustain focus for more than a few minutes
- You’re deciding which tasks deserve deep, uninterrupted attention
- You want to understand why some work sessions feel productive and others feel scattered
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 (Leroy, 2009)
- 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 | Characteristics |
|---|---|---|
| Deep | Writing, coding, analysis, strategy | High cognitive load, creates value |
| Shallow | Email, Slack, admin, scheduling | Low cognitive load, maintains flow |
The mistake is mixing them. Email during deep work ruins the deep work.
When to Apply
Single-task for:
- Creative work (writing, design, strategy)
- Complex problem-solving
- Learning new material
- High-stakes decisions
Batch for:
- Administrative tasks
- Communication (email, messages)
- Routine operations
Cross-Domain Applications
| Domain | Deep Work Example | Shallow Work Example |
|---|---|---|
| Health | Focused workout session | Logging meals |
| Wealth | Investment analysis | Bill payments |
| Social | Deep conversation | Quick check-ins |
| Meaning | Journaling, reflection | Calendar review |
Related
- Do Deep Work Protocol : The executable steps
- Environment Design : Reduce friction for focus
- Constraints : Attention as finite resource
The person who does one thing for 4 hours beats the person who does four things for 1 hour each.
Leroy, S. (2009). Why Is It So Hard to Do My Work? The Challenge of Attention Residue When Switching Between Work Tasks. Organizational Behavior and Human Decision Processes, 109(2), 168–181. https://doi.org/10.1016/j.obhdp.2009.04.002
Ophir, E., Nass, C., & Wagner, A. D. (2009). Cognitive control in media multitaskers. Proceedings of the National Academy of Sciences, 106(37), 15583–15587. https://doi.org/10.1073/pnas.0903620106