310

In my experience a USB plug needs a bit of pressure to go in the port. It’s enough pressure to make me wary that I might break it if I’m putting it in the wrong way. After reversing the plug, it becomes obvious that it does not fit at all. This observation allows me to flip it again and now apply more pressure with confidence.


189

In a washing machine the objects that are being washed move around. It's a dynamic process, that is unpredictable and always unique. Watching the movement is fun, it indeed gives a sense of control to the user, even if it is not actually required. Quite a few people even find it relaxing to watch the washing machine. The window also prevents users from ...


172

Here in Finland the main reason is this: Image source Road markings are used to denote speed limits but never as a primary mean. And as Jung Lee points out, re-applying road paint is labor intensive, especially here, as studded tyres usually erode most of the paint in one or two winters. Edit: The Finnish law actually states that road markings, such as ...


166

A Google search doesn't really provide me any answers but I do have some ideas on why the doors would close: 1: Time Efficiency (As stated by Andrew, Ruudt, and Angelo) Closing the door reduces the time the elevator needs, to move to a different floor when someone presses the button. 2: Safety (1) When a door stays open and a user approaches the elevator, ...


162

Short answer: Design commonly causes misalignment Most plugs or ports have a flared edge, beveled plug or some other design that allows for the orientation of the plug to be slightly off and still match. USB doesn't. Oftentimes, the first attempt will cause your plug to be aligned too high, slightly twisted, or some other orientation that doesn't allow it ...


154

Physical symmetry without symmetry of use I'm surprised that so many of these answers are addressing the consequences of poor design without discussing what made it a poor design in the first place. The issue at hand here is that the USB devices have a correct orientation and that correct orientation is indistinguishable from the incorrect orientation. In ...


145

It is a combination of manufacturing and usability... but mostly manufacturing. Doing a quick web search for "why are soda cans round" (Google does a decent job) yields multiple insights in the issue. But the only result you need to visit is engineerguy's YouTube video (you should also be Subscribed to engineerguy, because he is awesome). The Ingenious ...


138

This wikipedia page sums it up quite nicely https://en.wikipedia.org/wiki/Intentionally_blank_page Such pages may serve purposes ranging from place-holding to space-filling and content separation. And the reason I see it most often Intentionally blank pages are usually the result of printing conventions and techniques.... Book pages are often printed ...


134

Because, at the table, a shaker is entirely the wrong dispenser for sugar. Shakers are used to sprinkle small amounts of a substance over an area, which is exactly what you want for salt and pepper. Sugar is used to sweeten drinks by adding a relatively large amount, which is just dumped in the drink and not spread over an area. If you tried to do that with ...


130

Closing the door for the floor the elevator is on reduces the time, the elevator can serve another floor upon request. The time is saved due to omitting the door closing step. Considering that elevators usually serve more than two floors this speeds up the more frequent use case.


130

I am in the fast food business having owned five units for over 30 years but don't have a unit with two lanes. The reason for two lanes is a matter of timing from McDonald's research into this that I read years ago. (I am not with McDonalds.) It all comes down to timing and shaving 10 or 20 seconds off the time you wait in line is worth having. The slowest ...


119

Unfortunately such cable is not compliant with USB specification, as even in usb power delivery the data lines are used to negotiate power. You should not mark it with USB (or even USB-like) logo at all. Plug's distinctive shape is informative enough to be easily recognizable as in "where does this plug go". I concur with other answers suggesting lightning-...


108

In the event of a stopped dishwasher (due to electrical fault or buggy software or something) the water in the device streams out of ordinary drains inside, and the water sprayers stop adding more water. If you were to open it after it had shorted out, you aren't going to get soaked. That's not true of a front-load washing machine. If one of these is ...


108

You are totally right As with many other devices (eg the QWERTY keyboard) the hot/cold tap persists not because it's the most usable design, but because of: Cost since proper temperature control requires an electromechanical feedback loop design, or calibrated thermostatic valves which needs to be periodically adjusted or replaced. This drives up the cost ...


102

I think icons are the best possible way to convey the information about different flushing amounts. I see too much uncertainty by relying only on button relative sizes and ease of use. It can be a simple pictogram showing the tank in the relative size of water what will be flushed upon pressing that button. (source: sswm.info) Or any other icons that ...


94

Historically It is a simple fact that traffic signals were introduced in 1868. From The Origin of the Green, Yellow and Red Color Scheme for Traffic Lights: In London, England in 1865 there was a growing concern over the amount of horse-drawn traffic causing danger to pedestrians trying to cross the roads. A railway manager and engineer named John Peake ...


89

The important thing is not so much which direction is right, but that you make it visually clear which direction is 'on'. This can be done by lighting up an LED, by an icon on the display, changing colors, etc. It just needs to be very clear what state the machine is and that this button will toggle the state. This is how single direction switches (buttons) ...


89

Great question! This is an good case for microinteraction design. Microinteraction objectives In descending order of priority: Provide clear affordance for user to place card/wallet on reader Provide clear feedback that the user should hold the card on the reader until an outcome. Since this is public transportation, provide blind- and deaf- friendly ...


83

Excellent answers so far. I would attempt to connect the dots between recording and red button like this: Apart from the traditional warning usage, a red light has been used in many scenarios to represent on-going work - radio show room when on air, operation theater when operation is going on, etc. The reason behind that would be the same - it is highly ...


80

It appears to be dependent on country or region, as Wikpedia states in the article Light Switch: Up or down The direction which represents "on" also varies by country. In the USA and Canada and Mexico and the rest of North America, it is usual for the "on" position of a toggle switch to be "up", whereas in many other countries ...


79

The underlying problem, as I think we all know, is that the tactile feedback you get with an incorrectly oriented plug is hard to distinguish from the tactile feedback with a slightly misaligned plug. Given that, your question can be reformulated as: why do many (most?) people mistakenly assume the orientation is wrong when they actually just need to keep ...


78

The reason for the design was because of the technology at the time. Rotary Dial (Pulse dialing) To dial a number, the user puts a finger in the corresponding finger hole and rotates the dial clockwise until it reaches the finger stop. The user then pulls out the finger, and a spring in the dial returns it to the resting position. For example, if the ...


76

You can never beat straight text ("Power Only"); that way, there can be no confusion. That said, I actually have such a cable at home which has an icon very similar to this in a raised profile on the connector: It would be nice to look to the creator(s) of the standard USB icon for inspiration, meaning and thus cues for how to adapt it to mean "power only"...


69

Salt and pepper are (generally) used in smaller amounts. A sugar packet also is a sort of measuring unit; it's roughly as much as a sugar cube. That means that you can use it for coffee and tea without having to pay attention to how much you use. Sugar clumps faster than salt and pepper do, I think, so you don't want any tea/coffee steam to clog up the ...


65

Just looked up the answer, and quite a few places seem to have the same thought. In front load washing machines, the window is given to see what is going on inside. In the top loader machine, you can open it at any time even when the machine is on wash mode but you cannot do so in front load machine, for the water will spill if you open the window ...


63

OK, how about this? Should be understandable by everyone, irrespective of culture.


59

Is there any chance the label pictogram is actually 10x10mm? Guidance on Labelling and Packaging Version 2.0 - September 2016 states in section 5.2 (Size of the label and of the label elements) that for a package of capacity less than or equal to 3 litres, the pictogram (in this case the flammable hazard pictogram) must be not smaller than 10x10mm and if ...


57

Various hotels I have come across (though I remember that primarily from China) had simple lamps with the respective do not disturb and please clean room signs next to the door and accordingly labeled switches on the inside of the room to activate either of the exterior lights. It cannot be used by anyone other than the guest. It costs somewhat more than a ...


56

By holding onto the card, the user is clearly informed that their transaction is not yet complete. If the card was given back before any transaction, the user may be uncertain as to whether they are still authenticated. Giving back a physical piece of identity makes it absolutely clear that you have 'logged out'. There is a perceived and an actual security ...


56

Practical origins defined our tastes When car finishes became shiny (because they weren't always) [1,2] due to the availability of the required technology and paint materials, it was mostly for practical purposes - cost effectiveness, weather resistance, rain run-off, aerodynamics, ease of cleaning. Consumers found the attention-grabbing gleam of a shiny ...


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