Diarized
Buffer time
Buffer time is deliberately empty space left between commitments, so that one thing running long does not push everything after it. It absorbs the difference between how long work takes and how long it was expected to take.
Also called: breathing room, slack time
Where it goes wrong
People add buffers around meetings and not around work, which is backwards: a meeting has a hard stop and a task does not. A day packed edge to edge with tasks is not an efficient day, it is a day where the first overrun ruins the rest.
Diarized schedules the work you already keep in a to-do app into the calendar you already use, and shows you why every block landed where it did.