100 Things Every Designer Needs to Know About People, 2nd Edition

46 People are Worse at Multitasking than they Think

Many people think they are great at multitasking and even pride themselves on their multitasking abilities. But the research on multitasking shows that most people are worse at it than they think.

Most of the time what people are doing when they think they are multitasking is “task switching.” People can attend to only one task at a time. You can only think about one thing at a time. You can only conduct one mental activity at a time. So you can talk, or you can read. You can read, or you can type. You can listen, or you can read—one thing at a time. We are pretty good at switching back and forth quickly, so we think we are multitasking, but in reality most of the time we are not.

One Exception ...