What it does to the work

The one thing the four-minute reply is supposed to be good for is the work. Even if it costs you the evening, at least the job is better served. This chapter is about whether it is.

Start with what a reply written at ten past nine is like. You're at the end of a day. You're half watching something. You've got the question on a small screen, without the folder open, without the context. The reply is short, because it's on a phone, and it's slightly wrong, because you're not looking at the file, and in the morning there's a second reply correcting the first. Sandra Ohly and Alessa Latour surveyed 1,714 working people about work-related phone use in the evening and found it went with lower positive mood, and that what mattered most was why people did it. Those who used the phone in the evening because they chose to, for their own reasons, recovered better. Those who did it because they felt they had to felt worse. The four-minute reply is almost always the second kind. Nobody feels they chose to answer Priya. They felt the buzz.

Then look at what the reply does to the next day. Gloria Mark, Stephen Voida and Armand Cardello cut off email for thirteen office workers for five working days and measured what changed. Without email, people switched between windows less, stayed on each task longer, and had lower stress as measured by heart rate monitors. Thirteen people is a small study and the office had agreed to the experiment, so the finding is a demonstration, not a rule. But it points the way you'd expect. Email fragments attention, and the evening reply extends the fragmentation into hours that were meant to be whole. The work you do tomorrow is done by a person who never fully stopped.

There's also what the reply does to the thread. A question that would have been one exchange in the morning, with the file open and a clear head, becomes four exchanges at night, with a correction at eight. The sender now has four messages to read instead of one. The fast reply looked like service. It was noise.

The honest objection is that some evening replies are good work. If you've chosen an hour, opened the laptop, and answered properly, that's Ohly's autonomous kind, and it's fine, and it's a block of work rather than an availability. The four-minute reply on the sofa isn't that.

So the work isn't served. It gets a worse answer, later corrected, from someone more tired tomorrow, and it gets a thread nobody needed. The morning reply is the better one, on every measure I can think of.