Sprint is not a timeboxed event?

Last post 12:27 pm November 26, 2021
by Piotr Górajek
11 replies
Author
Messages
01:15 pm November 23, 2021

Hi,

You are the best of the best. One of the top Scrum Alliance trainers told me that since Scrum Guide 2020 Sprint is not a timeboxed event anymore. He claims that "duration and timeboxing" are different concepts.

I want to be open to the possibility that I'm wrong. Therefore, could you please explain it?

 

01:51 pm November 23, 2021

Yes, the guide only mentions timeboxes for three of the five events, with the Daily Scrum event and the Sprint event itself being left out; however, I believe that all events are still timeboxed. 

From the guide:  Sprints enable predictability by ensuring inspection and adaptation of progress toward a Product Goal at least every calendar month.  The Daily Scrum is a 15-minute event for the Developers of the Scrum Team.

Timeboxes ensure that feedback loops happen. 

To me, a duration could easily be seen as something dynamic which could end earlier or later than forecasted; whereas, a timebox is something that you work within and must stop working once the timebox has expired. 

02:04 pm November 23, 2021

For me too. Yet I'm discussing with "Lean Consultant & Coach TAC Member at Scrum Alliance". I'm not sure if I can post a link to another community without being banned here :)

I found this:

The Scrum Master serves the Scrum Team in several ways, including:

  • (...)

  • Ensuring that all Scrum events take place and are positive, productive, and kept within the timebox.

 

02:40 pm November 23, 2021

Looking at the Scrum Guide, it does appear that the term "timebox" was removed from the description of the Sprint. It was there in the 2017 Scrum Guide ("The heart of Scrum is a Sprint, a time-box of one month or less during which a “Done”, useable, and potentially releasable product Increment is created."), but is no longer there in the 2020 edition. Instead, Sprints are described as "fixed length events of one month or less"). Looking back, the term "timebox" for the Sprint was also used in the 2016, 2013, both 2011, 2010, and 2009 editions of the Scrum Guide. So, strictly speaking, the word "timebox" is no longer used to describe a Sprint.

Just because the word is used in the Scrum Guide doesn't mean that the word can't be used to describe the Sprint. A timebox is the period of time allocated to working toward a goal. Each Scrum Event has at least one goal or objective to reach. The desire is to achieve the goal within the timebox and the event does not proceed past the timebox. This seems to describe a Sprint. The Sprint ends after a fixed duration and the purpose is to work toward the Sprint Goal.

However, there is one difference between a Sprint and the other Scrum Events. Other events may end before the timebox is reached if the objectives have been met. A Sprint does not end until the timebox expires. I'm not sure that this nuance is enough to say that a Sprint is not a timebox, though.

It seems like there's no reason to not call the Sprint a timeboxed event. The only question would be if a timebox implies that you much work until the end of the timebox. If that is to be accepted, though, that opens some questions regarding timeboxing the other events and the implications of doing so.

02:49 pm November 23, 2021

 Thomas Owens According to scrumin:

"Timeboxing is allotting a fixed, maximum unit of time for an activity. That unit of time is called a time box. The goal of timeboxing is to define and limit the amount of time dedicated to an activity. Scrum uses timeboxing for all of the Scrum events and as a tool for concretely defining open-ended or ambiguous tasks" - https://www.scruminc.com/what-is-timeboxing/

I don't think this definition has evolved, regardless of Scrum Guide changes. 

 "The Scrum Master serves the Scrum Team in several ways, including: (...) Ensuring that all Scrum events take place and are positive, productive, and kept within the timebox" - Scrum Guide 2020

Scrum Master wouldn't be able to make sure that Sprint is kept within the timebox if Sprint was not a timeboxed event. Does it make any sense? If not, we should write:

"The Scrum Master serves the Scrum Team in several ways, including: (...) Ensuring that all Scrum events take place and are positive, productive, and kept within the timebox (except Sprint which doesn't have a timebox but a fixed length)" - Scrum Guide 2022

04:40 pm November 23, 2021

They are fixed length events of one month or less to create consistency. 

That is the second sentence in the current Scrum Guide section that describes the Sprint. While the word "timebox" is not used, I don't see how that could be not be interpreted to be a timebox.  Timebox is not a word defined in Merriam-Webster's dictionary nor any other online dictionaries I checked. But it is defined in many articles about agile.  The definition on this site is pretty consistent with all of the ones I found.  They all loosely define a timebox as a fixed duration in which work is accomplished. 

If you want to be literal about the definition, the Sprint is no longer referred to as timeboxed event.  However, it is referred to as an event that has a maximum boundary of time and that boundary can be shortened should the desire be present. 

Honestly, the fact that a Scrum Alliance trainer is touting this makes me trust anything coming from them even less.  

04:41 pm November 23, 2021

I don't think Sprint is a time-boxed event.  As the definition "They are fixed length events of one month or less to create consistency" Sprint shall always be the same length, however, other events can be held with different length, but no more than the time boxed duration respectively.

06:32 pm November 23, 2021

I don't necessarily accept Scrum, Inc.'s definitions as correct, but in this case, I don't see any problems with it. This definition doesn't say one way or another what happens if the objectives of the event are met before the timebox expires and would leave it up to each event. Using this definition of the timebox, it wouldn't preclude defining events like the Sprint Planning, Sprint Review, and Sprint Retrospective from ending before their timebox if their objectives have been met while requiring that the Sprint run to the end of its timebox.

It seems like "timebox" should apply to the Sprint, as well as to the Daily Scrum, which are the two events that don't explicitly use the term in their definitions.

08:02 pm November 23, 2021

The Scrum Guide says that each Scrum Event has to be kept within the timebox, and the Scrum Master needs to assure that this happens. No exception is made for the Sprint.

The Guide says that Sprints are fixed length events of one month or less, so that gives you the maximum possible duration of a Sprint timebox.

02:04 am November 24, 2021

A Sprint could be cancelled if the Sprint Goal becomes obsolete. Only the Product Owner has the authority to cancel the Sprint.

Although the Scrum Guide says less about cancellation thesedays, this mechanism for ending a Sprint earlier would appear consistent with other uses of "timebox", in that there is a maximum duration for the event to be kept within, but when appropriate, an event can end early.

 

Timeboxes ensure that feedback loops happen. 

To me, a duration could easily be seen as something dynamic which could end earlier or later than forecasted; whereas, a timebox is something that you work within and must stop working once the timebox has expired. 

I agree with Scott Anthony Keatinge's assertions, and I feel he explained it well.

 

To take it further, I believe the metaphor of a physical box can sometimes help.
Just like a physical box can contain an item up to and including the inner dimensions of the box, a timebox can accommodate an event of duration up to and including the length of the timebox.

Often a physical box isn't completely filled, and although the extra space may seem like a waste, it can also be wasteful to artificially fill the box with things that aren't needed.
Likewise, it is often best to end an event once it has achieved its purpose, rather than artificially fill it with activity that isn't needed, just to take it to the end of the timebox.

If your house is full of boxes that are only partially filled, it might lead you to question whether you are buying boxes of the correct size, or organizing your stuff in the most effective manner. You might get smaller boxes, or choose to put more things in each box. There is an improvement to be made in operational efficiency, but it comes at the cost of having less spare room in each box, if and when it's needed.
For Scrum Events, the equivalent might be a choice to either shorten the timeboxes of the events, to look for more opportunities to make use of the available time (e.g. more/deeper conversations with stakeholders at the Sprint Review), or to accept this unused time as an acceptable overhead, because of the added flexibility it provides.
 

03:42 pm November 25, 2021

For me Timeboxed event means maximum duration of the event when you finish earlier then the timbox that is ok.

For a Fixed length event means the exact duration. 

for example the time box for the sprint planning event is 8 hours but you are finished after 5 that is ok.(

You finish all your PBI that you had planned for your sprint within a 4 week sprint in 3 weeks in this case you dont finish your sprint after 3 weeks but select additional PBI to develop with in the last week of the sprint. (Fixed Length)  

12:27 pm November 26, 2021

IMHO changes were introduced to enhance clarity for extra limitations put on Sprint and Daily Scrum timeboxes, or rather durations. Before it may not be clear why Sprint timebox can not be ended before time runs out, while different events have such property. On the other hand, Daily Scrum can be ended before timebox runs out, but is fixed at 15min regardless of Sprint duration.

I believe that matured practitioners are already aware of that nuances and are perfectly fine to call all time limits in events as timebox. However, for new comers it may be good that this word is  dropped for Sprint and Daily Scrum, as it aids their ability to understand concepts (hopefully) 🙂