Once we've learned about our audience, what the business expectations are, what data we're working with and how the information could be organised we, through a process of sense-making and synthesis need to create something tangible, to test our learning and assumptions thus far. As well as helping us express our thoughts more clearly, a prototype can help to explain our ideas to stakeholders, development teams and audience alike.
Types of prototypes
Prototypes are like dresses, you need the right one for the right occasion, well I don't, but you understand what I'm saying. I like to break them down into a few appropriate use cases. Often the same artefact could be used with different stakeholders for different reasons at different points in the project. It goes without saying that as your ideate the fidelity of your prototype becomes richer.
I use prototypes:
- During synthesis - to test assumptions as a designer
- For user test with audience
- To facilitate sign-off with business owners
- As documentation, to explain ideas to development/implementation teams
It's important to note that a prototype isn't the only tool you can use, but for me they tick a lot of boxes - a prototype is worth a thousand pictures!
Prototypes to test design assumptions
As a designer I'm a very visual person. Making something tangible helps test my assumptions of how a design might work in the hands of a user. For me the best way to do this is via a prototype, in various fidelities but ideally something I'm able to play with in it's final destination - most of the time this will be a browser.
I'm coming round to the view that the more finished this prototype is, the more problems will be caught early and solved, not pushed down the line to hit the project later. While I might start out with something very rough, I like to move towards a very 'high-fidelity' prototype, including final visual and text treatments - while some will argue this is beyond the role of UX, I believe the final look and feel of a product is very much part and parcel of the experience. The colour, size and final placement of a button can drastically alter it's usability and the chance of key interactions not having the correct impact. To me this sounds like UX.
Prototypes for user testing
Obvious really, the more 'real' the prototype the better the better quality the feedback be. Yes this can take extra time, but it's totally worth it. If everything else in your process has been covered diligently then you really shouldn't be distance out with your prototype. If you're less confident with your research, or ability to synthesise this information, then by all means test earlier with lower fidelity designs to validate your thinking.
Prototypes for design sign-off
When working with business people not familiar with the design process or design procurement in general, sign off can be a headache (please note that this is my problem as a designer, rather than the business people I work with). For them, being asked to give the go ahead to spend a lot of money developing software from looking at a bunch of black and white boxes on a page (wireframes) is a big ask. These people risk a lot of their credibility signing on the dotted line. I believe we should be making them as comfortable with these decisions as possible. For this I like to use a process I call 'guided facilitation', the outcome of which will inevitably something tangible to sign off against - In my experience a real life HTML/CSS prototype works best.
Prototypes as design documentation
Just as prototypes are great for understanding your own design assumptions, they're also a very rich way to explain exactly how your project goals should be met to the development and implementation teams. Having a tangible reference allows development teams to have a dialogue with design and understand exactly what they're building. These browser based designs remove most ambiguities in a project and allow for much better clarity in conversations within the project team throughout the cycle of development.
Possibly the most important takeaway: At any of the above points you have the opportunity to revisit your designs and iterate. Frankly I would be slightly worried if after all of the above I didn't come across new data/comment/inspiration that lead to a tweak in what I had designed - I'm not expecting wholesale changes, but incremental updates. And at the end of these updates I wouldn't say no to another round.