Even the simplest of products can be designed poorly.

Take, for example, a water dispenser. It’s not much more than a hot water faucet, cold water faucet, and drip tray. But add on a few extra features, like a child safety lock and room-temperature water, and suddenly there’s a lot more room for poor user experience. Here, I evaluate the user interface for a new water dispenser in my college library.

Context / Problem

There’s been a water dispenser in the lobby of my college library for years. It used to look like this:

The old water dispenser.

Using this was simple: lift the red tab for hot water and the blue tab for cold. But then one of the tabs broke, and the school opted to get a new, more modern dispenser:

The new water dispenser.

At first glance, it doesn’t look too bad. In fact it looks sleeker, more durable, and high-tech. As it turns out, however, the new dispenser had a few pain points, and compared to the old dispenser, the user experience was worse.

How It Works

I first gave the dispenser a try. For cold water, using it was simple: put your water bottle under the spout and push the blue button. For hot water, though, there were actual instructions:

The instructions on the top of the dispenser.

I also drew a diagram mapping out the parts of the dispenser. Note that the indicator lights above the red and green buttons are always on.

Sketch of the water dispenser.

User Research / Feedback

I conducted a few interviews with a friend to figure out what problems users were encountering. We made a few observations:

No one had trouble getting cold water. No one knew what the green (room temperature) button was for, and the instructions (which say “ambient water”) don’t help. Those who wanted hot water struggled with getting past the safety lock, or did more than they needed to, especially if they didn’t notice the instructions. The placement of the spout and tray made it difficult for people with taller bottles or water bottles with narrow openings to see if their bottles were filled or not.

Personas

Using these observations, I created two personas representing the two most commonly seen categories of users.

Warm Winnie. (Avatar created by Freepik.)

Cool Calvin. (Avatar created by Freepik.)

Storyboard

From my personas, I created a storyboard for Winnie.

Storyboard depicting some of the pain points of the water dispenser.

Proposed Solutions

With my personas created, I now have a better idea of what to focus on: the unintuitive process for hot water. So, here are some possible redesign solutions.

Solution 1: Get a new dispenser without a hot water safety lock.

Yes, this isn’t a redesign, but the main problem is that the new water dispenser has unnecessary features. Hot water safety locks are there mostly for kids — and there are hardly going to be kids in a university library. Also, who really needs room temperature water? Less is more.

If that doesn’t work, and you want to keep the new water dispenser design, but with a few tweaks…

Solution 2: Provide more user feedback.

One of Nielsen’s usability heuristics is “visibility of system status”. This means that the user should know what’s going on at all times. This new water dispenser often fails this heuristic because there’s barely any indication of whether the dispenser is going to dispense cold, hot, or “ambient” water. If the indicator lights were off by default and only turned on when the hot/ambient water is activated, then the user would associate red light=hot water, and so on, and would run into less errors. Bonus points for auditory feedback, like a beep or clunk.

Solution 3: Change the blue button.

Alternatively, instead of having a plain blue button as the dispense button, why not have a button that changes color according to water temperature? Blue for cold, red for hot, and green for… erm, “ambient”. Even if it were just a neutral-colored button with lighting around its border, it would still be more informative than the current setup.

Solution 4: Use a push paddle for dispensing and keep a button for unlocking hot water.

For a more drastic redesign, why not get rid of the dispense button altogether? Have a push paddle that you push the water bottle against to dispense, and have a button to unlock hot water. This keeps things more consistent; i.e. buttons do one thing (unlock) and the push paddle does another (dispense). The water would default to cold, and turn hot if you hold down the button while you push your bottle against the push paddle. The drawback for this solution would be the limited height of the dispenser; the push paddle might not work with taller/narrower water bottles.

Conclusions

Through this case study, I found that user feedback is invaluable. There are only so many problems you can discover by yourself, and conducting even a couple of interviews will drastically improve your knowledge of the product’s design issues. (For example, short people couldn’t read the instructions on the water dispenser at all!)

Finally, even a simple product like a water dispenser can have a lot of pain points, and that you should always define the full scope of your problem — in this case, finding a water source in a university library — before jumping to a solution.