Bug Blindness

davidmckenna 162 points 67 comments August 30, 2026
danluu.com · View on Hacker News

Discussion Highlights (20 comments)

sidewndr46

This is rather interesting to read. But it reinforces something I've seen in my career. The majority of users of software I've helped build, they use it in ways that are mind bending to me. Workflows I would never think of, that somehow do what they need. The second one is most software contains bugs. Users that expect to get things done simply choose workflows to avoid the worst consequence of those bugs very quickly.

theandrewbailey

Bug: this blog has no max-width. Lines of text will grow infinitely long with width.

ChrisMarshallNY

I’m really anal about the Quality of my own software, and tend to be hard on others’ software (doesn’t make me too popular). > I've had multiple jobs where directors/VPs/execs/etc. sometimes ask me to evaluate something when they want an actual opinion from someone who is relatively likely to notice issues (and fix them or drive fixes for them if necessary). I’ve had the experience where I need to be asked, and even then, if my opinion isn’t “ist güt,” it’s often ignored. When someone makes a proposal, I tend to immediately see the potential issues, and used to point them out, and suggest workarounds or mitigation strategies, without being asked. Not the happy path. I get accused of being “negative,” my suggestion is shitcanned, and I’m shunned. I’ve learned to just keep my mouth shut, and if the situation calls for it, start quietly preparing for when the wheels fall off. I have also learned to never say “I told you so,” as that is a petty and vindictive statement. Doesn’t help at all.

encomiast

I had to give up when the first example of a "bug" that the author could see, which others are blind to, was search results. "In some cases, people sent me their actual search results. In every such case, the search results did not contain a good result that I could see" Software that does not meet expectations, especially in a field like search, which is basically a long running war between SEO and search engines, is not a 'bug'. That's like saying there is 'bug blindness' in the publishing industry because when I pick up a random book, it sucks, even though others think it's fine. Sure, maybe something is wrong, could even be improved, but lets save the word 'bug' for something more specific.

nicoburns

Blackboard is definitely a really strong contender for the worst software I've ever had to use. When I was in uni, I went so far as to write an alternative that scraped the content from blackboard and published it on a site that I could actually browse sensibly. They were paying exorbitant amounts of money for the license too.

aljgz

Did I write this? I choose tools I use, configure them, report bugs, and occasionally contribute fixes. But when I can't, I work around them, yet never get used to the workaround. "Habitual mitigation" does not happen in me, and it's partly intentional. I have created bad software in the past, but when I saw how people work with it, I could not be proud. Learned to look at software like a user, and don't want to unlearn that. I believe (or maybe I hope) software will be democratized and people will start to demand good software.

transcriptase

My absolute favorite bug is the one where the “cancel your Amazon Music subscription” is seemingly the only one of what must be tens of thousands of UI elements in the Amazon app that simply loads a blank white screen no matter what. What are the odds!

spiderfarmer

Is there also a thing called Readability blindness?

kmoser

> At times, I've tried to see if I can get a job somewhere where I just fix quality issues all day. This has never panned out, due to some combination of this not being a very high priority and it also not being a normal role that companies have a role for. I'm pretty sure dedicated QA roles are a thing at many companies.

moyix

Parts of this reminded me pleasantly of one of my favorite John Regehr posts, "Operant Conditioning by Software Bugs" https://blog.regehr.org/archives/861

sgentle

I think there are two opposite causes here: either an overly-aligned or completely unaligned mental model. For developers, bug-blindness tends to be because their mental model is so close to the system's model that both have the same blind spots, and the developer can't effectively think outside the system (the classic "QA walks into a bar, orders 0 beers, orders -1 beers, orders 0.999 beers" vs "customer walks into a bar, asks where the bathroom is, bar immediately bursts into flames"). On the other hand, a common way for regular people to interact with a system is they just... don't have a model. None at all. Like, they click a thing and see what it does, and if it doesn't do what they expect they shrug and click something else. The horror of seeing a non-software person using a software system is realising that they usually cannot tell the difference between expected and unexpected behaviour, because they don't really form expectations in the first place. The computer is more genie than machine. You can see this in the article: "Google Docs added some kind of delay such that the typing you do into the title box right after you open the doc gets overwritten". That's a developer forming a model of the system. The lay alternative is to simply learn that sometimes when you type in a box, the text appears. Other times, it doesn't. If it doesn't, you try again. You don't need to understand the system if you abandon the assumption that the system was designed to be understood. And, in practice, the widespread plagues of shitty engineering, anti-features, and lack of respect for the user often combine to make that model the more information-theoretically optimal one. In that sense, the very thing that makes us miserable is our perverse need to treat Google Docs as an engineered product rather than a cross between a djinn and a symbiotic fungus.

syngrog66

Long ago I realized I had the ability to see race conditions in source code, at least more easily/accurately than others on average. It was helpful when reviewing the code of others, esp more junior. And I once briefly considered getting a custom T-shirt made with the words "I see race conditions." (in the spirit of the famous scene from The Sixth Sense with "I see dead people.") and wearing it to the office during formal code review meetings. But a friend talked me out of it when he pointed out it might get misinterpreted as being something racist rather than having to do with threading and concurrency. The whole "I see bugs where others do not" reminded me of that same phenomenon.

socalgal2

I'm with danluu on this, at least as far as the headline, and not actual details. I run into 10 to 20 software bugs a day (feels like more). If it wasn't for the all the private data I'd leak I sometimes wish I could just put my phone and computer on screen capture for a week, with input data (keyboard/mouse/touchpad/screen) and then come back and post the 100 bugs I hit that week. I've run into the MacOS one mentioned, getting a black screen on opening the lid. I've also run into iOS Camera app failing to open the camera. I've run into the iOS keyboard only using 80% of the width of the phone (all the keys smaller). No idea how to fix that. Closing the keyboard and re-opening does not. And killing the app, whatever app, is out because I'm in the middle of filling out a form and don't want to have to start over. I've had the phone's screen freeze quite often recently, no response to any finger presses. Locking and unlocking the phone recovers. This one is new (started happening 1-2 weeks ago) Common/not-common. Any app that uses the phone camera to scan things (checks/ids) almost always fails in one way or another. Doesn't recognize the thing or times out like the only way they tested was in perfect conditions in their office and never tried with real users.

bediger4000

Great post. Pins the tail on the donkey. As a lifelong Unix and Linux user, when I was forced to use Windows at work, this kind of thing struck me profoundly. Windows users just didn't notice how crippling the whole experience was. They'd write it off as "user error" when Word autocapitalized strings weven if auto caps was turned off, things like that, similar to "natural running motion".

__MatrixMan__

I feel cursed with the opposite of this. I can't seem to go 12 hours without finding a bug in software which it's not my job to test. It's all so awful. I waste a lot of time trying to figure out how to report these bugs, because they offend me. Just once I'd like to believe, for a little while, that this industry has produced something worth being proud of.

m3kw9

A bit of perfectionism helps with esp UI bugs. A little flash, slight unusual pause, trying different ways to break the code..

kid64

> I get that people who are fans of things tend to be blind to the thing's faults. Wow, there's Obsidian, Kagi, and Apple in a nutshell.

omoikane

> humans have a high ability to ignore negatives in things they're a fan of, including (and often especially) their own work I thought this is due to the "backfire effect", because humans perceive criticisms of things they like as threats. https://theoatmeal.com/comics/believe

ghastmaster

>I thought this had something to do with how I use computers but, over time, I've realized that it's mostly that people are hitting the same bugs and don't notice. I suspect I know why they do not notice. See below. >it works well, etc., but when I open up the thing and try it, it's in a state where the thing only works if you do quite a few non-intuitive workarounds. I suspect most people are so inept at navigating UI because even a good UI is not intuitive to them. A bad UI is equally not intuitive. They do not know it is a bug because everything is a bug to them. I can use a novel UI and figure out where to find what I need to do very quickly. In my experience with lay people, they can use the software for a decade longer than me and still not understand some of the capabilities and navigate to utilize them as I can within a few minutes or small amount of research. Shoutout to https://grumpy.website/ . Love it.

coder-pm

Hah in the AI era I noticed the agents are worse than the average person at noticing bugs. Agents use their own scale to decide if something is a success even if the output is broken. Agents are bug-blind to their own work. The consequence is that spotting bugs is now the key reviewer skill. The human’s job shifts to catching what the agent is blind to in its own work.

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