When something that was working, suddenly doesn't work when demoing to others
52 points by atarian 10 months ago | 50 comments- flerchin 10 months agoThis is part of a constellation of symptoms that I attribute to the Senior Engineer Field Effect. Other symptoms may include being unable to demonstrate misbehavior, losing the requirements out of your head, and solving a bug that has been bugging you for hours.
All by the mere proximity of a Senior Engineer.
- flerchin 10 months agoLosing the capability to type while she watches.
- flerchin 10 months ago
- dinkblam 10 months ago> The phenomenon that something which was previously working correctly, suddenly does not work correctly when one tries to demonstrate the operation to others.
the same word is also used for the reverse situation, i.e. if something that did not work suddenly works when trying to demonstrate the failure.
think bug reporting e.g. at the car mechanic, warranty claims, etc. if you try to show a reproducible bug to others, it suddenly vanishes...
- jprete 10 months agoIs the word only for unpleasant surprises, or for all such situations, even when the surprising outcome is also a good one?
- dinkblam 10 months agoi've never seen it used for pleasant surprises. its basically if you want to show something (even something that does not work, like the engine-not-starting) and the demonstration does not work as expected.
- namibj 10 months agoThey only have to be "unpleasant" in some aspect, for example because you now annoyed/bothered you team lead. The unexpected behavior itself can still be desired, with the unpleasantness restricted to the demonstration itself.
- namibj 10 months ago
- dinkblam 10 months ago
- jprete 10 months ago
- khazhoux 10 months agoWhat's the word for this:
* My code doesn't work and I can't find the bug even after over an hour
* I add a few lines of <whatever code>. Now it works!
* Now, just for comparison, I remove all the code I just added (or, at least I think I reverted back to previous state). But now it still works.
???
- maicro 10 months agoThat could probably be called a Heisenbug[0]: A bug that disappears or alters its behavior when one attempts to probe or isolate it.
Though it depends on the cause - as others in this comment chain said, if it's just that the file isn't actually being updated between tests, but adding a new line forces an update/recompile/etc., I'm not sure what you'd call it.
- nope1000 10 months agoOnce I added a comment and my bug went away. That was when I went home for the day.
- marcosdumay 10 months agoThere's the alternative:
* The program works flawlessly
* Somebody finds a bug on the code that is executed in a test
* The relevant test now fails consistently
Both are probably because you changed something on the environment when you looked at the code.
- omoikane 10 months agoAnother common cause is that the code you were looking at wasn't actually the code you were running. Between "I added this line and then I removed this same line, and now it works", the executable might have been recompiled.
- bobthepanda 10 months agohot reloading can cause weird behaviors like this in particular
- bobthepanda 10 months ago
- omoikane 10 months ago
- woranl 10 months agoI get that a lot, just have to restart that Docker desktop to push the saved changes to volume.
- oneshtein 10 months agoClock skew?
Makefile (or a similar build system which uses timestamps) + a problem with wall clock -> stale files.
- flerchin 10 months agoChoose an editor with autosave to fix this one.
- recursive 10 months agoNow you have two problems.
- recursive 10 months ago
- colkassad 10 months agoDevOps
- rozenmd 10 months agocache?
- 10 months ago
- maicro 10 months ago
- rendall 10 months agoThe English-language term "demo effect" means the same thing.
https://quentin.delcourt.be/blog/2020-01-22_demo-effect/
https://www.urbandictionary.com/define.php?term=demo%20effec...
- knoke 10 months agoOne should note: In contrast to other such composites, this is often used in everyday life.
- AdmiralAsshat 10 months agoWhat's the equivalent word for "Your computer suddenly becomes slow and unresponsive, you try to open Task Manager (or run `top` in a terminal) to see what's bogging down your resources, but the resource monitor itself refuses to respond for a few seconds until the lag vanishes, at which point the utility finally renders and everything under the CPU/Memory utilization appears normal" ?
- _nalply 10 months agoThat's a temporary system stall when some critical part of the system is overloaded or blocked, usually the disk.
Or an out-of-memory condition, the system recovers when the OOM killer has killed a random process. If you were lucky that process was your game hogging ressources and when it went away the system recovered.
And for impressive German words? "Systemaufstauung mit urplötzlicher Lösung" (system bottleneck with sudden resolving), "Speicherüberlastung" (memory overload) or "Prozessabmurkser" (process terminator).
Note that I invented these words (oder auf gut Deutsch, ich habe mir diese Wörter aus den Fingern gesaugt).
- eska 10 months agoIf you anticipate that this will happen when you open task manager, possibly because it has happened before, you start chanting in German “watch me, I’m about to pull a trick 17!” before opening task manager, having ensured that the whole room is paying attention whether you succeed. When people ask how you knew or why it worked you just shrug smugly to hide the fact that you don’t actually now, and let everybody bask in your aura.
- _nalply 10 months ago
- adityaathalye 10 months agoI wrote this prayer to appease the Demo Gods [1]. Though one might pray, the demo can fail.
O Lambda the Ultimate, bless we who are in this demo...
[1] Slide no. 5 here: https://github.com/adityaathalye/slideware/blob/master/n-way...That our core be functional, and our functions be pure. That our data be immutable, so we may know the value of values. That our systems be composable, so they may scale with grace. That their States only mutate in pleasantly surprising ways. That the networks and servers stay up. Well, at least through this demo. For otherwise, nothing lives, nothing evolves. In the name of the \alpha and the \beta and the \eta... \(\lambda x.x x\) \(\lambda x.x x\) ; eternally(edit: formatting)
- hateful 10 months agoA related thing that happens a lot is when the demo is way slower than it was when you were testing it. But at least this one can be explained by screen sharing applications adding latency to your refresh rate. It really is slower when you share your screen!
- aa-jv 10 months agoWhats the antipode to this, where, as a programmer going to investigate a user bug, my mere presences makes the bug disappear, and the user frustrated at trying to reproduce it for me?
Because this happens a lot to me these days, no kidding. The bug happens, some user delights in calling me over, I take a look, they simply can't reproduce it, I walk away - they get the bug again - and, yeah, I kind of have to race ahead of things to understand the nature of the users situation.
Happen to anyone else? I don't think its quite like Vorführeffekt, and is maybe a bit more like Daseinsvermögung oder etwas ..
- 10 months ago
- LeifCarrotson 10 months agoIt's fascinating to me how German composite words encapsulate an idea like "[failure attributed to] demonstration effect" in a way that just saying "demonstration effect" in English often fails to accomplish.
I also love how German often has useful opposites - schadenfreude vs fremdschamen, for example.
On that note, is there an opposite to this, where someone observes that something's not working, they call in the expert to diagnose the problem, and it functions perfectly under demonstration?
- wjholden 10 months agoWe sometimes use the term Houdini in my field for difficult-to-reproduce problems, but not exactly as an antonym to Vorführeffekt.
- xg15 10 months agoGerman dev here, we frequently filed this just as well under Vorführeffekt, probably even more frequently than the "standard" variant.
- xg15 10 months ago
- wjholden 10 months ago
- ChrisMarshallNY 10 months agoAKA "The Wrath of the Demo Gods."
Now, I have a word for it...
- iambateman 10 months agoI believe the English translation for this is “uhhhh”
- bobthepanda 10 months agoFor presentations, always have a backup video.
- netcoyote 10 months agoIn my company we call these "Show & Fail".
They often occur because we'll say "I just want to fix this one thing before we build the demo". We call this type of commit to the source control system a "break-in" instead of a "check-in".
- rpnx 10 months agoBack in university, my compsci security project didn't work on the university wifi for some reason, if we used google chrome. Firefox worked fine. Some kind of weird proxy broke the website. But to this day I don't know exactly what happened.
- breadwinner 10 months agoPrevious discussion: https://news.ycombinator.com/item?id=21170732
- colechristensen 10 months agoI don't think this one is going to make it into English. Vorführeffekt is a bit hard to pronounce.
- jszymborski 10 months agoDoesnt seem that hard to mangle into english:
Vore-fyur-effect
- skirmish 10 months agoFohr-fyur-effect [ˈfoːɐ̯fyːɐ̯ʔɛˌfɛkt]
Letter 'v' is called "fow" in German and is pronounced as sound "f".
- wjholden 10 months agoThe "v" is pronounced as an "f" in German. So, "fore-fyur-effect." English speakers could say "forfeit effect" a few times and then change the middle syllable.
- skirmish 10 months ago
- jszymborski 10 months ago
- satisfice 10 months agoI call it Singing Frog syndrome.
- happytoexplain 10 months agoI'd have more use of a term with the inverse meaning.
- knoke 10 months agoSelf-fulfilling prophecy?
- happytoexplain 10 months agoI mean attempting to demonstrate something broken, only for it to work properly.
- copypasterepeat 10 months agoWouldn't this term still apply? If the goal of your demonstration is to show failure, and then that succeeds, that makes your demonstration a failure.
- knoke 10 months agoAs already said: Vorführeffekt is neutral and could mean both: success and failure. But the opposite of „a performance with an opposite than expected outcome“ is something that comes out exactly as it’s supposed to be without intervention, right? ;)
- copypasterepeat 10 months ago
- happytoexplain 10 months ago
- knoke 10 months ago
- MattPalmer1086 10 months agoI always heard this called "The Law of Demo".
Definitely a thing!
- mrcode007 10 months agoWhat would it translate to? Inspection effect?
Edit: demo effect?
- daft_pink 10 months agoWas this word invented by google
- 10 months ago