ComparisonScaling Software Development - ZeroBlockers vs Waterfall: Which product development framework is better for you?

The principles behind the two frameworks are completely opposing. Waterfall assumes that the solution defined upfront is the best solution and that the team should focus on delivering it. It is more efficient to build a solution in one go rather than breaking it up into smaller pieces if you are confident that the solution is correct.

ZeroBlockers assumes that it is not possible to know how people will react to our products upfront so we need to identify the best solution through experimentation. We break up the solutions into small iterations so that we can get feedback quickly and iterate on the solution.

Waterfall assumes that there is no value until the full solution is delivered. This means that teams are incentivised to build the full solution before releasing it.

In contrast, ZeroBlockers forces teams to release early and often by making it a core metric. The framework gives teams strategies for breaking down solutions into working iterations so that teams can achieve very short lead times and get the critical feedback required to improve their products.

The other core difference regarding efficiency is that Waterfall focuses on how a single team operates but often the biggest challenges are how teams work together. As companies scale the number of dependencies between teams increases and this slows down delivery. ZeroBlockers focuses on removing these dependencies.

Waterfall assumes that it is possible for a business person to define the best solution upfront and that it is possible for the business to effectively communicate the solution in full to the team.

ZeroBlockers takes a completely different approach because the core principle is that you cannot know how customers will react to new features until they have them in their hands. It is not fair to ask a business person to specify the outcome of a feature because we don't know. We all have ideas that sound great but few of them work. Therefore solution evaluation and iteration are integral parts of the process. We empower teams to identify the best solutions and then hold them accountable for outcomes.

Shared code is subject to the tragedy of the commons. Each team has a tight deadline so they need to cut corners at the end. Waterfall assumes that you can plan around code dependencies but as companies scale the number of dependencies increases. You get cascading impacts of delays because every project is interdependent.

ZeroBlockers works on the principle that you cannot manage around dependencies - you have to remove them. Shared code and environments are two of the largest dependencies so we remove them by giving each team their own code base and environment.

Burnout isn't caused by challenging targets or high workloads. It is caused by being held to targets that you can't control such as an unrealistic deadline that was imposed on you. By giving teams autonomy over the way they achieve the product goals you are putting them in control. We can still set challenging stretch targets but, once teams can control how they achieve the targets, this can energise rather than cause burnout.

Waterfall is based on the principle that it is more efficient for specialists to focus on their area of expertise. By defining a clear process specialists can do their work and handover to the next specialist. This works exceptionally well when completing repetitive tasks such as on a manufacturing assembly line.

ZeroBlockers recognises that software development is a unique activity. We never build the same thing twice - you can copy and paste code! This means that each handoff is unique and context gets lost when handing over via documentation. The core principle is that it is more efficient to have cross-functional teams working from problem through to solution when you are working on unique problems.

Waterfall is easier to implement because it is the standard way of working across most IT departments. It therefore requires fewer changes and has more support.

ZeroBlockers involves changes across the business - because software is integral to our products today - not something just tacked on. This means you need more buy-in to get started. But you can start small - one product, one value stream. With over 10 years of UXDX content and case studies, there is also a large body of resources to assist in the rollout of the framework. It might be tougher to implement but it will deliver better outcomes.