Every recipe says to pour a little water, wait, and then carry on. For a long time I poured, counted to about ten, and got bored. The cups were fine, mostly, and once in a while one of them tasted hollow in a way I could not explain.

For two weeks I timed it. Same bag, same grind, same kettle, and only the pause changed. I wrote the result down before looking at the timer again.

PauseTotal timeWhat I got
10 s2:40Uneven, sour edge, some days flat
30 s3:05Rounder, sweeter, the same every morning
60 s3:30A little dull, nothing wrong with it

The difference was not that thirty seconds made a better cup. It made the same cup twice, which is what I actually wanted. Fresh beans puff up and push the water away; give them half a minute and the rest of the pour behaves.

What I do now

I pour about twice the weight of the coffee, stir once, and leave it alone until the timer says thirty. It is the only part of the morning I do not try to speed up.