Use the C.F.A.S. Method for Google User Interface (UI) Questions

google interviews Dec 24, 2021

Oftentimes, user interface (UI) questions have a lot of ambiguity. In this blog post, we will discuss a commonly asked UI question presented in Google interviews. This UI question is typically for candidates going into design, research and product roles within the company. Here’s an example of what they might ask: 

Imagine you have three different UIs and you want to know which one is best. What would you do?

The goal of this type of question is to uncover your problem-solving capabilities. I highly recommend following a structure that will allow you to stay organized and on point during your answer. One great method is the C.F.A.S. system, which stands for “Clarify, Framework, Assumptions and Solution.” Let’s break it down one section at a time…

Item #1—Clarify

First, you should be asking clarifying questions of your interviewer. There may be a number of items that need clarification. Regardless of whether or not they answer your questions, this will demonstrate the importance of thinking before solving. In addition, you can get your interviewer more connected to how you think. 

Pro Tip: Clarifying questions need to be either/or or yes/no questions. Otherwise, you are asking for structure, not clarification.

Understand the complexity of the question being asked. In this UI example, you would want to ask if you are comparing one specific feature of three different user interfaces. Or, are you testing three completely different UIs? Obviously, that is a big difference to know and will establish the complexity of the scenario. You may also ask about which stage this testing is taking place. Is it in the research, testing or production phase?

Ask what details you are actually looking at when comparing these three different UIs. These questions will give you better clarity of the hypothetical project. This will allow you to craft your response in a way that addresses all the key issues.

Item #2—Framework

Second, provide a framework to help break down the problem into fundamental pieces. Essentially, you are providing your interviewer with a high-level overview of the concepts that would be interesting to cover in your solution. In this answer, you could utilize any of these four frameworks or a combination of any of these items.

     Operational Concepts: Goals, Historical Data, Risks, Users

     UI Focus Areas: Visual Design, Functionality, Usability, Performance, Accessibility, Compliance

     UI Focus (Deep Dive): Clarity, Simplicity, Relevancy, Consistency, Discoverability, Productivity, Usefulness

     User Focused: Needs/Wants, Challenges/Pain Points, Motivations, Conversion

When thinking about any of these concepts, utilize the items that you are most comfortable with and will be the easiest for you to expand on. Your clarifying questions from step #1 should also help you narrow your focus on the concepts that matter most.

You can watch my full video on this topic below for a more detailed walkthrough of this step:

Item #3—Assumptions

Third is assumptions. Skipping this step will make it hard to have success when answering any hypothetical question. Remember it is critical that assumptions are presented after your framework. They will allow you to have more focus when delivering your solution. And, this will create visuals to establish way more connectivity with your interviewer. This is especially important with a design, research or product role at Google.

Key issues to cover with this particular UI question will be walking through the methodology of the testing, as well as focusing on the number of users. State how you would test the three different UIs and paint a picture of your process. Briefly cover the important steps and details.

Item #4—Solution

Ideally, any answer to an open-ended question should have multiple solutions. Each solution should be two minutes or less and should be tied back to one framework concept. For example, maybe the first solution focuses on usability. And by making good assumptions, you will really be able to dig into this item. 

After each solution, check in with your interviewer to see if they would like to dig deeper into the item you just discussed or move onto something else. So let's say you started with usability, you could ask your interviewer if they wanted to dive deeper into concept A or B that you mentioned in that solution, or move onto performance, for example.

The C.F.A.S. method is a strong interview answer technique that can apply to many different procedural interview questions. It is a great solution for approaching a UI question with Google or another high-level tech company.

For more information about interview coaching techniques, sign up on Practice Interviews or follow my YouTube channel for weekly video posts and interactive live streams.

Jeff H. Sipe

Jeff has interviewed over 1000 people in his career and previously spent five years working at Google headquarters in Silicon Valley. You likely found Jeff through YouTube and you will find the same level of dedication in his one on one practice interview sessions.

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