Why does jumping between tasks cost more time than it feels like?

You are not doing two things at once - you are flipping between them, and every flip charges a fee.

The brain cannot fully run two demanding tasks in parallel. When you switch, it has to drop one set of goals and rules and load the other. That reload takes a fraction of a second and leaves more errors behind. The switches feel instant, so the lost time stays invisible - but it adds up across a day.

You answer one Zalo message mid-report, then stare at the screen for a few seconds trying to remember which sentence you were writing. That blank moment is the switch fee.

Doing tasks back to back is slower and sloppier than finishing one before starting the next, even when it does not feel that way.

Batch similar work and silence pings while you focus - you reclaim the time those invisible switches were quietly eating.

Every task switch is a toll booth: you slow down to pay, even on a road that looks clear.

Learn the idea and practice English at the same time.