TL;DR
Really gets in the way of having a lot of information? Why?
In theory, yes. Because the capacity of human attention is limited. The user may not realize what they should, and even if they do so may generate too much cognitive effort for more continuous interaction.
There are studies or at least consistent information that show that one really is better than another?
There are numerous. But more general studies serve as a standard approach. The best study for you will be the one you do with your users using prototypes of the product that prepares for them.
Why is hiding operations better? And if that’s not why they’re adopting it?
It might be better to hide because it facilitates the user’s local interaction (they don’t have to worry about what isn’t important in the current context). However, the user should never need to remember much information. Again, human capacity is limited.
Is there any way to facilitate discovery, facilitate access to operations without "fouling" the screen?
There are numerous, all using some of the human senses (after all, the user needs to be able to perceive past information). Games, for example, make methodical use - and befitting fantasy (i.e., prior knowledge of the user) - of sounds. The classic example is the sound of swords colliding in the Age of Empires, which indicates that a battle begins outside the user’s screen. Mobile apps also vibrate the device. Anyway, you don’t necessarily need to use the screen to pass on some information.
There are exceptions where we should not apply one of these philosophies?
Certainly there is. The most obvious is building applications for the blind. In this case no matter the amount, the screen is not the best way to transmit the information. It may seem like an extreme example, but the idea is that these exceptions stem from your own analysis of your users, with their preferences, expectations and needs.
Original and more complete version
There are two things that are very important to consider in designing interaction with a product: appeal and engagement.
The appeal is directly related to user preferences and aesthetic issues of the product, such as how nice, beautiful and curious it looks like. It’s a first level of interaction, where the user chooses to start using the product. On the other hand, engagement, although it also includes attributes of preference and aesthetics, has a stronger relationship with satisfaction in the use experience. It is a more continuous contact, in which the user chooses to continue interacting with the product. If the expectations created in the first contact with the product are met or exceeded in a positive way in the continuity of contact, usually have the engagement.
Appeal, Amount of Information and Cognitive Effort
The appeal is closely linked to curiosity, which is a basic human need to understand the world. This need arises from and leads to interaction. We humans interact with the world not only by altering it through our actions, but also by realizing the changes that we ourselves and other agents make in it. It turns out that the mechanism of attention (which filters out the enormous amount of sensory data we continually receive from the world and decides what is relative or not according to our intentions) is limited. It is estimated* that each person can process 126 bits of information per second, which means that we are able to pay attention to a maximum theoretical three simultaneous conversations (if we can completely ignore everything else, such as the internal perceptions of our own organism).
* The source of this information is the psychologist’s work Mihaly Csikszentmihalyi, in the book Flow: The Psychology of Optimal Experience. Those who wish to read on the subject of interaction, attention and motivation, in a way (perhaps) a little easier, can read this my article on fun.
If you don’t believe in this limitation of attention, take the test and try to count the
number of passes of the white team in this famous video. :)
That’s why evolution has made the brain so interested in slightly unknown patterns. When observing something that has nothing new, this something is simply uninteresting (we already know the subject, we do not care because it will not help the organism to do better in actions with the world). However, on the other hand, if this something is completely unknown and unable to be at least compared to something else known, it is chaotic and consequently also uninteresting. That is why a TV screen with only static, which has a lot of information from the point of view of Information Theory, is simply boring and does not cause even a start of appeal. But that’s also why very difficult puzzles, as appealing as they are initially, make engagement difficult because users simply can’t figure out how to proceed.
All this theoretical bla-bla is to demonstrate that there is an ideal point in the amount of information to be displayed. It should be enough to cause appeal and excite curiosity (and don’t just think about games; an alarm in a factory control system needs to be able to attract attention quickly!)but cannot exceed the natural limitations of human beings to the point of causing discomfort and thus hinder engagement. Even if a lot of information is understood and causes appeal, it can require a lot of cognitive effort and thus simply tire the user. That’s why there we Principles of Usability is preached, among other things, to prevent the user from having to remember the path in the menus to a command, for example.
Note, however, that the mere existence of much information is not always bad. Bad is flooding the user with all of it at once, making him unable to extract something useful from it. The result of a Google search, for example, has a lot of information, but it is spread over easily navigated pages. And, mainly, it is very clear to the user that this possibility exists (he realizes that there is more data than what he is currently seeing). In fact, here is the link to the physical effort of the next topic: the user may not care so much about having to navigate to the next item many times, as long as this browsing action is relevant and simple.
The example you used in the question (the full field interface) is intrinsically worse because the user doesn’t know what to do next than because he has available all that information. This fantastic article, called Desmystifying UX Design, has much more relevant information in this regard.
Ergonomic Engagement and Effort
Ergonomic or use effort (such as the number of clicks) is more relevant to engagement than appeal. This is natural, because during the first contact the user has not used the product properly and only has expectations about how it will interact with it. The cognitive effort, treated in the previous topic, is already started from the first contact, when the user seeks to understand how the product works.
It is a tendency to believe that too much physical effort undermines engagement because it makes the user simply get tired of interacting with the product. For example, the Nintendo Wii boxing game may seem very interesting at first contact (it has great appeal), but after a few games the physical tiredness of having to constantly punch air can make the experience less satisfying than imagined. Still is not a universal truth, because everything depends on the preferences and expectations that are created in the users during the appeal. There are users who have immense satisfaction in spending physical effort, and will surely realize that this is the type of game for them from the first interactions.
In other words, it is not the effort itself that undermines engagement, but the perception of its relevance by users. In the article I quoted earlier on UX demystification, there is the example of the greater number of clicks on an Assistant interface (Wizard), but which is perceived as facilitator by users because it does not require great physical or cognitive effort individually, do not burden the user with questions, and allow it to reach the goal gradually.
I unfortunately no longer have the reference of this study, but the mechanism of raising the electric glass of cars with just one touch came from tests of Japanese automotive companies with their users, in which it was observed precisely this fact. In early versions, users were required to keep pressing the button for the glass to go up or down. As fast as the glass went up, users always complained that the mechanism was too slow (even if it was much faster than turning a crank, as it was done until then). It turns out that to keep pressing the button means to perform physical effort, even if much less than turning the crank. But the perception of the result by that effort was very small, comparatively. While holding the button - a task so simple as to be ridiculous - time seemed to pass more slowly because the feeling of idleness (idleness) was huge. That’s why the Japanese created the auto up/down from a touch. :)
Incidentally, there are studies who also observed this phenomenon of the relationship between action and time. After intentionally distorting the perception of time ("fooling" participants with watches that pass more quickly), it was found that even tasks considered very boring (such as counting match sticks!) are experienced as more pleasurable because of this perception of flying time...
And how to Plan Interaction
The best way, according to all the UX sources I have studied and my own experience, is to evaluate the interaction directly with users, mainly using low fidelity prototypes (as built on paper). The low fidelity of the prototype facilitates construction (in terms of cost and time) and prevents the designer from attaching to the product created (this interface was so cute and the user did not like it... ah, it is he who does not know what he wants... my Precious!). In addition, the evaluation allows to observe the critical points in all aspects discussed above. On that subject, I suggest also read this other question about what are Wireframes, Mockups and Prototypes and the book Interaction Design: Beyond Human-Computer Interaction.
Would you have an example of each of the two situations? In order to better understand the "philosophies" you are quoting. And their real differences, difficulties and operations "hidden".
– Fernando Leal
I’m trying to find one before or after to post, if you find something cool, I’ll edit it. Show it well. But I speak in general terms. Just so you don’t leave without any example: to get to http://answall.com/help/mcve. you need 4 clicks. You need less first. Another example is the use of tabs instead of screen divisions. I see applications that go so far as to require switching screens to compare information. While understanding this is mobile, Windows 8 has raised this: http://ux.stackexchange.com/questions/31207/ Gmail is a good example of how it’s changed.
– Maniero