How a bad UI message prevented us from resolving a 5 days feature downtime

This article is about a UI message in our platform that was confusing enough that it prevented us from resolving a 5 days downtime on a feature. We could have resolved it much faster, but because the message was confusing it made things worse. I hope that UI experts and engineers (like us) could benefit and get an insight of how some things are confusing to the users.


Our service for visualizing animated and interactive 3D assembly instructions is used by one of the well known robotics education platforms At FLLCasts there are instructions of LEGO robots and mission models from the FIRST LEGO League robotics competitions. Here is an example instruction –

On the left you see the message “Downloading initial steps…’


5 days ago a user wrote a ticket to us with a question:

“Why can’t I download the instructions?”.

I naturally responded to the user “Well, you can’t because this is how we’ve built them to work. They are open in the browser and they can not be downloaded. What are you trying to do anyway?” (oh, my ignorance)

The user replied in the ticket

“I just want to build them.”

Obviously there was a great miscommunication between us. The user was trying to build the instructions, but was using the term “Download”. Why? Well, because we taught them so.

5 days later I found out the following thing. Some of the instructions were not working. When users were visiting them we, as “ignorant engineers” were showing a message that said “Downloading initial steps…” while the instruction was loading. In our engineering mind we were really downloading the instruction to the browser. Some of the steps of the instruction were downloaded from the server to the client, which is the browser.

When the user got in touch with us he said “Hey, why can’t I download the instructions”.
When asked this question I assumed in the ticket that the user wanted to download the instructions on their file system and be able to open them from there in an offline mode. Which is generally what “Download” means. I made a really wrong assumption of what the user was trying to do. He was trying to load and view the instructions. He was not trying to “Download” them. But we were telling them that we are “Downloading” the instructions and they naturally used this term.

The implications

For 5 days about 5-6% of our instructions were not working correctly. We could have resolved this the right way if I paid a little more attention to what the user was asking in the ticket or if the message was “Loading initial steps…” instead of “Downloading initial steps…”

You learn something every day.