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From motorised suitcases to dog massagers: the wackiest gadgets at this year’s IFA
by Stefanie Lechthaler
Why does the progress bar get stuck at 99 per cent?
22/6/2022
Translation: Patrik Stainbrook
When installing a program on your computer, setup rarely runs regularly. The progress bar often freezes just before the end. Our culprit is the complexity of the task – as well as the human psyche.
«Update and Shutdown» just ran on my HP work laptop. I was annoyed before the update even started, as it always takes longer than you’re told at the beginning. And, as always, the bar moved at different speeds, only to get completely stuck at 99 per cent.
But why?
Progress indicators are first and foremost good for our psyche. Imagine for a moment that you’re in line for an ice cream. As long as the line is moving and you’re advancing, the wait is relatively bearable.
For exactly the same reason, when installing programs, there are numerical or visual representations that are supposed to show you that something is happening and thus reassure you. However, this only works as long as progress actually occurs. Like standing in line: if you don’t move for a while, you get impatient and your mood gets worse.
The problem: «On the one hand, the effort for a detailed reading isn’t worth it in most cases, as it exists primarily for the mental wellness of the user. On the other hand, as a programmer, you can never really make a progress bar reliable anyway. That’s why the whole tool is implemented in a very simplified way,» says Martin Gasser, Lead Software Engineer at Digitec Galaxus AG.
The machine can’t do much more than guess
«Unless Internet speeds fluctuate greatly or there’s even a network interruption, the duration of the download itself can be estimated relatively well, but when installing, differences are massive,» says Remo Vetere, Senior Frontend Engineer at Digitec Galaxus AG. «If the duration was overestimated, the progress bar simply stops halfway through. If the duration was underestimated, the bar freezes.»
The fact that this happens so often at 99 per cent is precisely due to this simplified implementation of progress indicators. They aren’t even «smart» enough to get stuck somewhere in the middle, he says. «Initially, the duration is roughly estimated. Then percentages are counted forward at regular intervals. If your installation takes longer, the bar simply stops at the last possible moment, i.e. at 99 per cent, until the task is completed,» Martin explains to me.
An interplay of fact and psyche
Still: here, too, our psyche plays a role: «As a user, you notice when something is going on too long. If your installation takes less time, you just move on without giving it much thought,» says Martin.
So, in short, the progress bar works like this: in most cases, it’s implemented in a very simplified way, as a detailed version simply isn’t worth it. The tool is only there to show us users that everything is running in the background and to spare our fragile nerves – at least as long as the bar doesn’t freeze at 99 per cent forever.
Why does the hand of a station clock usually stop short? Why do they have popcorn at the movies? And why are drinking glasses not allowed in waste glass containers? Everyday life holds many puzzles in store, which I try to solve at irregular intervals. If you have a burning question but no time to research it, send it to me by mail. I like doing the dirty work.
My life in a nutshell? On a quest to broaden my horizon. I love discovering and learning new skills and I see a chance to experience something new in everything – be it travelling, reading, cooking, movies or DIY.
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