What's the point of delaying SCHEDULED items from displaying in org-mode Agenda?

Question

One may set org-deadline-warning-days to have DEADLINE items show up a default number of days before the deadline in the agenda, or one may do it on a case-by-case basis by adding, e.g., -3d to the DEADLINE timestamp.

Now, using the same warning notation -3d on a SCHEDULED item produces the reverse effect: the item is not added but skipped from the Agenda view for that number of days.

From the Org-mode manual:

 If you want to _delay_ the display of this task in the agenda, use
 `SCHEDULED: <2004-12-25 Sat -2d>': the task is still scheduled on
 the 25th but will appear two days later.  In case the task
 contains a repeater, the delay is considered to affect all
 occurrences; if you want the delay to only affect the first
 scheduled occurrence of the task, use `--2d' instead.  See
 `org-scheduled-delay-days' and
 `org-agenda-skip-scheduled-delay-if-deadline' for details on how to
 control this globally or per agenda.

What can this be useful for?

My understanding is if you want to start working on an item and you schedule it for a specific date, you want to start seeing the item in the agenda at least on the scheduled day, and may be even earlier, but definitely not later.

Am I missing something?

Answer 1

The "--1d" style delay (which only delays the first occurrence of a repeating event) is useful when you will be unable to complete a repeating task on the scheduled day (because you're out of town, for example) but don't want to reschedule the other occurrences.

If you are have

* Do This
  SCHEDULED: <2015-01-01 +1m>

to do something on the first of each month but are going to be out that day you could reschedule it to one day later (the 2nd), but then the repeat will schedule it for the 2nd of the next month. You have to reschedule a second time to get it back to the first. Instead you can use

* Do This
  SCHEDULED: <2015-01-01 +1m --1d>

Which will hide it in your agenda for a day and then when you do it schedule the next occurrence for the first of the next month, removing the delay.

Answer 2

As the manual says of hiding scheduled items from the TODO list:

Some people view a TODO item that has been scheduled for execution or have a deadline (see Timestamps) as no longer open. Configure the variables org-agenda-todo-ignore-scheduled, org-agenda-todo-ignore-deadlines, org-agenda-todo-ignore-timestamp and/or org-agenda-todo-ignore-with-date to exclude such items from the global TODO list.

While it isn't my way of working, I can see how this might appeal to some. It also isn't directly speaking to the context of your question.

However, in that context, I could imagine someone wanting to suppress the scheduled item from their agenda until some time after the scheduled date. (I've not played with it, but I would expect that the TODO item would still come up in views like the log view and the TODO list.) Such a way of working would involve thinking of the agenda as a list of items on fire, rather than a list of all items.

Not to my taste and likely not to yours, given your comments. But, one glory of org mode is that it doesn't enforce its model of task management anywhere nearly so much as do most other tools that I have tried. (It is sort of like a tool for building your own tool.)

Answer 3

In addition to what @erikstokes has mentioned, this feature is also useful to me in the following scenario:

I have a todo list for things to be done today. I also track scheduled tasks and routines with "SCHEDULED". Every day, I check both lists in a single agenda view to determine what to do.

The agenda, however, get cluttered when I put my project plan into the org file because, during project/feature plan, I set SCHEDULED and DEADLINE for each sub-task. Those dates are only part of feature plan, I do not need reminders for them as I just tackle them one after another.So, to keep the agenda view "clean", I may make use of this feature:

Set a delay time for the SCHEDULED attribute, "SCHEDULED: <2015-09-24 Thu -1m>" for example, so that the project tasks will not show up until one month after the scheduled date, but at that time they should already be marked DONE and hence do not show up.