Sprint stretch goals are harmful.

 I was listening to a podcast episode: Command Your Focus and Attention on What Really Matters with Chris Bailey and noticed a really good analogy.

"What allows traffic to move forward at a solid space is how much space exists between the cars on the highway"


What struck me about it is that I can use it to explain team productivity in different organizations I was a part of. Some of them tried to pack the sprint with tasks to the full, but in some, it was ok for the team to pick a 'safe' amount of tasks so that they could be sure to accomplish them.


Before I was thinking about the benefits of slack time that allows the team to work on important things (not only urgent) and to have space for urgent things if they show up. The great feeling of accomplishment when you finish last scheduled task day before the end of the sprint and can tackle additional bug or two or the confidence to spend additional hour making code more maintainable before finishing the task.


Now with the traffic analogy, I think that what whole team or even organization productivity depends heavily on not taking too much work to do. Creating space between tasks allows work go smoothly - otherwise, you end up with hectic fire-fighting and you're always behind schedule.


Another important effect is on creativity. The only way to make sure that humans can be creative is a playful environment. It has to be fun. In my experience, too many tasks and too high expectations create additional stress that kills creativity when it's most needed.



More reading:

https://www.quora.com/Why-is-it-that-in-traffic-jams-some-drivers-leave-a-huge-distance-between-themselves-and-the-next-car - Please take a look at the comments - you can notice people arguing against it as it's not intuitive!

https://www.thekguy.com/surprising-benefits-slack.html

http://trafficwaves.org/