Context Switching
Multitasking is a myth. Rapid sequential tasking is a cognitive tax.
The 20% Penalty
When you switch from Task A to Task B, cognitive residue remains. The brain cannot instantaneously clear its working memory. Research demonstrates that for every additional project or context you juggle simultaneously, you lose 20% of your total cognitive capacity to the friction of switching.
This is why calculating your context switch cost is critical. If a notification pulls you away from a complex report to read a Slack message, you don't just lose the 30 seconds it took to read the message. You lose 23 minutes of deep focus recovery time.