When making any significant change to a team or organization, deciding whether to take a big bang or incremental approach is important. Both of these approaches–and hybrids in between–can work. Big bang and incremental approaches mark the two ends of a continuum of how organizations make a change. The decision is almost never straightforward and organizations often struggle with how they should approach change. The decision process begins by defining big bang and incremental implementation approaches in between the two ends so they can be compared.
Big Bang Implementations
A big bang adoption of a process or system is an instant changeover; a “one-and-done” type of approach in which everyone associated with a new system or process switches over en masse at a specific point in time. For example, most of the bank mergers I participated in were big bangs. The systems were all cut over on a specific date (lots of pizza and coffee was required for the cutover weekend) and the next business day all of the branches and ATMs began the day using a single system.
Big bangs are always the culmination of a lot of specific activities including planning, coordination, software changes, data conversions, and reviews. All of these activities are focused on making the big bang successful. Individually, the steps have little to no value if the final step fails.
Big bang changes are sometimes equated to “bet the business” scenarios: if the change doesn’t work, everything needs to be backed out or significant business impact will ensue.
An incremental approach focuses on defining identifying and implementing specific pieces of work. These pieces are generally smaller standalone pieces of work that progress an organization toward an overall goal but not generally all parts of one specific cohesive project. For example, quality or process programs often use a continuous process improvement model in which practitioners identify changes or improvements which are then captured as part of a backlog and prioritized for implementation. This type of work is sometimes called continuous process improvement. In this scenario, lots of individual pieces of work accumulate over time to deliver a big benefit. Incremental changes generate a fast feedback loop which delivers enhanced learning. The small changes typically found in incremental approaches are useful for experimentation.
The term ‘phased adoption’ can have alternate meanings. The first (and in 2017 the most common meeting) is to break implementation into smaller pieces so that the organization has use of functionality sooner. This is closer to an incremental approach than a big bang. Phased approaches break a bigger project into smaller projects so the adoption will happen in several steps. After each step, the system is a little nearer to be fully adopted. Phased differs from incremental generally in scope and the types of work in the backlog. For example in bank mergers, one phase might be to convert checking accounts and trust accounts in another phase. In an Agile adoption, a phased approach might be to transform one team after another in a serial fashion.
The second possible use of the term is the famed waterfall approach in which analysis is completed before design all the way to implementation. This approach is far less common than it was in the late 20th century before the Agile movement. However, make sure you check by asking how the word phased is being used.
Which implementation approach makes the most sense will always depend on context. The right choice requires understanding the goal of the change, resources available to make the change and above all else the organization’s culture. The choice is not as stark as big bang (everything at once) or incrementalism (lots of continuous little changes) although these are the choices most often considered.
In the next entry in this theme, we will explore the pros of the big bang approach.