"I have to answer straight away"

A lot of switching is driven by messages, and behind the messages is a belief that a quick answer is expected of you. If you leave an email for two hours, someone will think you're slacking, or something will go wrong.

Occasionally that's true, and there are jobs where it's the whole point. Chapter 14 is about those. For most office work it's worth testing, because I think the belief is stronger than the facts.

Look at the last fifty messages you received. For each one, ask what would have happened if you'd replied ninety minutes later than you did. For most of them nothing would have happened. The sender fired it off and moved to something else, and they weren't watching the clock. Many messages don't need a reply at all. A handful were urgent, and it's usually obvious which ones, from who sent them and what they say.

Some of the expectation is of your own making. If you always reply in two minutes, people learn that you do, and begin to rely on it. Then a two-hour gap does look odd. The habit has trained your colleagues, and their trained expectation now seems to justify the habit. It can be retrained in a few weeks, and chapter 17 suggests how.

There's evidence that the alternative is easier to live with than it sounds. Kostadin Kushlev and Elizabeth Dunn asked 124 adults to spend one week checking email only three times a day and another week checking as often as they liked. In the week of limited checking they reported lower daily stress. You might have expected the opposite, that leaving email unchecked would be the stressful part. In this study the constant checking was.

Dealing with messages in batches has a further advantage, which follows from chapter 3. Answering email is a task with its own rules. If you do thirty in a row, you load those rules once. If you do them singly across the day, you load them thirty times, and each time you unload whatever else you were doing.

There's a fair objection here. Your manager may really expect instant replies, and not everyone is free to set their own terms. That's true, and I wouldn't advise a silent rebellion. It's usually better to have the conversation. "I'm trying to protect a couple of hours each morning for the report. If something's urgent, ring me." Most managers, asked directly, would rather have the report on time. The ones who insist on instant replies to everything are getting worse work from their whole team because of it, and it can be worth telling them so.