Separation of Concerns
Working by the “scrum book”, sprint is also a release unit, in which you want to complete all the effort you committed to your clients and demonstrate it at the end of the sprint. Well, not in my book. Sprint should be remained an internal unit of time. Sprint is used for planning, for doing and for reflection, to make the team work better over time. It doesn’t mean that your customers will enjoy adjusting to your schedule.
I prefer to leave release cycles outside, as they are external unit of time. You need to adjust them to your customers, not the other way around.
Let’s say that you picked 3 weeks as a sprint size after considering “big enough, small enough” values. If you tie sprint and release together, that means that your clients will see things every 3 weeks. That might be fine, but it won’t allow you to challenge yourself to reduce release cycles. Even worst, the customers might demand a shorter release cycle to earn confidence in your delivery. A dangerous move, in my opinion, is to reduce the sprint size to match desired release cycle. This move might violate the “sprint should be big enough to avoid unacceptable overhead of planning/reflection” principle. Yes, your customers will be happy but your developers won’t. It won’t last. You want both internal team and external customers to be happy and enjoy a process that pushes them forward rather than pushes them around.
What is a Version?
Version is just a bunch of capabilities with a specific target date attached to it. Version is easy to communicate out: “we plan to allow a user to upload image, crop it and update his profile image in version 1.1, which is targeted to July 20th”. Basically, for each targeted date you specify a list of features, enhancements, reports etc. The customers gets to say when the versions should be aimed for, according to their needs.
What does it mean about Sprint Demo then?
Well, if the release cycles are shorter than sprint cycles then the Sprint Demo will become a show off by the team to each other rather to your customers. Obviously, you may want to add another “Release Demo” meeting for your customers (and maybe include the team in it). By doing Sprint Demo internally, the teams will get the chance to see what’s going on “on the other side of the corridor”. Oh, did I mention that this is also fun? It allows the organization to collect valuable internal feedback to make sure our users will love our product as much people who wrote it!