Tesler’s Law: The Key to Balancing Complexity in Web Design and Development

Have you ever wondered why some websites or apps are easier to use than others? Why do some products make you feel frustrated, confused, or overwhelmed, while others make you feel satisfied, confident, or delighted? The answer lies in how well the designers and developers of these products have applied the principles of user experience (UX) and user interface (UI) design.

UX and UI are two facets of web design that work hand-in-hand. While UI focuses on the user interface design, UX covers the overall user experience as they interact with your product or service.

One of the most important concepts that UX and UI designers need to understand is the law of conservation of complexity, also known as Tesler’s Law. This law states that every application has an inherent amount of complexity that cannot be removed or hidden. Instead, it must be dealt with, either in product development or in user interaction. This poses the question of who should be exposed to the complexity: the designer, the developer, or the user?

What is Tesler’s Law?

Tesler’s Law was coined by Larry Tesler, a computer scientist and former vice president of Apple. He observed that every application has a certain level of complexity that is determined by its functionality, features, and goals. This complexity cannot be eliminated; it can only be shifted from one place to another.

For example, a website that allows users to book flights online has a lot of complexity involved. This complexity can be distributed in different ways:

• You can put more complexity in the product development stage. This means writing more code, using more advanced technologies, and spending more time and resources to create a website that is simple and intuitive for the user.
• You can put more complexity in the user interaction stage. This means writing less code and relying on the user’s knowledge and skills to figure out how to use your website.

The trade-off between these two approaches is what Tesler’s Law is all about. There is no such thing as a simple or complex product; there is only a product with a certain amount of complexity that is allocated differently.

Why does Tesler’s Law matter?

If you put too much complexity in the product development stage, you might create a product that is easy to use but hard to build. This might result in higher costs, longer timelines, lower performance, or lower reliability.

If you put too much complexity in the user interaction stage, you might create a product that is easy to build but hard to use. This might result in lower satisfaction, higher frustration, higher abandonment rates, or lower retention rates.

The goal of UX and UI design is to find the optimal balance between these two extremes.

How can you apply Tesler’s Law?

• Know your users. Understand who your target users are, their needs and goals, pain points and preferences. Conduct user research using interviews, surveys, personas, scenarios, etc.
• Know your business. Understand your business objectives, value proposition, competitive advantage, and brand identity.
• Know your product. Understand what your product does, how it works, and who it serves. Define your product scope, features, and functionality using user stories, user flows, wireframes, prototypes, etc.
• Test and iterate. Validate your assumptions using usability testing, A/B testing, analytics, and feedback. Measure performance using conversion rates, retention rates, and satisfaction scores.

Conclusion

Tesler’s Law is a fundamental principle of UX and UI design that states that every application has an inherent amount of complexity that cannot be removed or hidden. By finding the optimal balance between product development complexity and user interaction complexity, you can create products that are both easy to build and easy to use.

Bibliography

[1] “Law of conservation of complexity,” Wikipedia, 2021.

[2] D. Saffer, “Larry Tesler Interview,” Designing for Interaction Website, 2010.