Back in the 1990’s, it wasn’t uncommon for people to check code into the repository that didn’t work. Sometimes it wouldn’t even compile.
In the department I was in, there was one developer, who started regularly checking in code that didn’t compile. Let’s call him Bob, because I don’t actually remember his name. He’d check something in that was broken and we’d have a talk with him. He’d promise to not do it again and yet within days it would happen again.
This went on for weeks, and became a real source of tension within the group. Bob insisted that he was being careful and that everything worked before he checked it in and yet every couple of days, one of his commits just wouldn’t compile on anyone else’s machine.
We all assumed that Bob was just being sloppy. There was certainly precedent for that as he’d been sloppy in the past and it was reasonable to assume that he still was.
It was more than just an assumption though. We had become fixated on one specific solution and no matter what other things we might have observed, we couldn’t shake this idea off. We were convinced that there was no other reason for the build to continue to break.
“The concept of fixation describes how we can hold on to our initial diagnosis despite strong contrary evidence, by deploying a variety of tactics to shield ourselves having to think about the implications of the contrary evidence.”
— Psychology Today
Fixation is very similar to confirmation bias, although is considered to be different. It’s a time where we hang on to our beliefs just a little too stubbornly.
We had become fixated on the idea that Bob was just being sloppy and for weeks, we couldn’t let go of that. Finally, someone started considering other options and after some fairly intensive debugging, it was determined that he had a flaky network card on his machine and that the commits were occasionally being corrupted during check-in.
Bob hadn’t been at fault at all; replacing his network card completely fixed the problem.
This is the problem with fixation. We were so sure we knew what the problem was that we didn’t even consider other options.
It’s easy enough to brainstorm other possibilities once we realize that we’re fixated. The hard part is recognizing that fact in the first place.
See also: This paper showing that the use of an AI image generator results in fixation: “we found that support from an AI image generator during ideation leads to higher fixation on an initial example. Participants who used AI produced fewer ideas, with less variety and lower originality compared to a baseline.”