THE DESIGN OF EVERYDAY THINGS

Notes

These were the original notes I took many years ago, and I don’t recall the exact version the page numbers come from.

p.ix

Warning Labels are signs of design failure

If you think something is clever and sophisticated, beware - it is probably self-indulgence

p.9

Affordance refers to the perceived and actual properties that determine just how the thing could possibly be used

When rail shelters had glass, vandals smashed it.  When they had plywood, vandals wrote on it.  Planners are trapped by affordances of their materials

p.13

Fundamental principle of designing things for people (1) Provide a good conceptual model (2) Make things visible

p.17

Perhaps the designers thought the correct model was too complex, that the model they were giving was easier to understand.  But with the wrong coneptual model, it is impossible to set the controls.

[ Simplifying is not simplifying if it puts the system model at odds with the conceptual model]

p.21

If a feature is in the genome, and if that feature is not associated with any negativity, that feature hangs on for generations.

p.22

Whenever the number of possible actions exceeds  the number of controls, there is apt to be difficulty

p.39

Everyone forms mental models to explain what they have observed [religion?].  In the case of the thermostat, the design gives no hint as to the correct answer.  In the absence of external information, people are free to let their imaginitions run wild as long as their mental model accounts for the facts as the perceive them.

If you think that a room will heat faster if the thermostat is turned up all the way to the max,  you are wrong.  It is just an on/off switch

p.53

The Seven Stages act as design aides:

How easily can one:

p.54

Not all of the knowlede required for precise behavior has to be in the head, it can be distributed - partly in the head, the world, and the constraints in the world.

p.62

Constraints reduce the number of options of the assembly of 10 components from 10! (~3.5M) to a manageable number.

p.78

wherever labels seem necessary, consider another design

p.81

The difficulty of dealing with novel situations is directly proportional to the number of possibilities

p.83

Affordances can signal how an object can be moved, what it will support, and whether anything will fit into it’s crevices, over it, under it.  Where do we grab, what parts move, and which parts are fixed.

p.84

Physical constrains are made more effective and useful if they are easy to see and interpret, for then the set of actions is restricted before anything has been done.

Physical, semantic, cultural, and logical constraints constrain our world.

p.85

Semantic Constrains rely upon our knowledge of the situation and of the world. [Lego driver must have windshield to protect his face]

Cultural issues are at the root of many of the problems we have with new machines: there are as yet no accepted conventions or customs for dealing with them.

p.100

The results of ANY action should be immediately apparent

p.103

One of the virtues of sounds is that they can be detected even when attention is applied elsewhere.  But this virtue is also a deficit, for sounds are often intrusive.

p.114

When you build an error-tolerant mechanism, people come to rely upon it, so it had better be reliable

p.115

Human thought…seems more rooted in past experience than in logical deduction.

p.119

If there were a thousand similar events, we would tend to remember them as one composite prototype.  If there were just on discrepant event, we would remember it, too, for by being discrepant it didn’t get smudged up with the rest.  But the resulting memory is almost as if there ahd only been two events: the common one and the discrepant one.  The common one is a thousand times more likely, but not to the memory; in memory there are two things, and the discrepant event hardly seems less likely that the everyday one.

p.128

Most major accidents follow a series of breakdowns and errors, problem after problem, each making the next more likely.

p.129

Although it may not at first seem to be relevant in design, [social pressure] has strong influence on everyday behavior.  In industrial settings social pressure can lead to misinterpretation, mistakes, and accidents.

p.131

Designers make the mistake of not taking error into account.  Inadvertently, they can make it easy to err and difficult or impossible to discover error or to recover from it.

  1. Understand the causes of error and design to minimize those causes.
  2. Make it possible to reverse actions - to “undo” them - or make it harder to do what cannot be reversed.
  3. Make it easier to discover the errors that do occur, and make them easier to correct.
  4. Change the attitude toward errors.  Think of an object’s user as attempting to do a task, getting there by imperfect approximations.  Don’t think of the user as making errors; think of the actions as approximations of what is desired.

p.134

It is important to think through the implications of that cost [of normal behavior, for a forcing function] - to decide whether people will deliberately disable the forcing function.

p.140

The designer shouldn’t think of a simple dichotomy between errors and correct behavior; rather, the entire interaction should be treated as a cooperative endeavor between person and machine, one in which misconceptions can rise on either side.

p.143

In the world of sales, if a company were to make the perfect product, any other compan would have to change it - which would amke it worse - in order to promote its own innovation, to show that it was different.  How can natural [Evolutionary?] design work under these circumstances?  It can’t.

One negative force is the demands of time: new models are already into their design process before the old ones have even been released to customers.[Try to give hard products characteristics of software]

p.144

Many of the useful refinements are being lost… All the folklore of design has been lost with the brash new engineers who can’t wait to add yet the latest  electronic gimmickry to the telephone, whether needed or not.

p.156

Designers often become expert with the device they are designing.  Users are often expert at the task they are trying to perform with the device

p.158

Design is the successive application of constraints until only a unique product is left

p.164

A toaster offers affordances for danger.  The location, the risk of burning a finger, and the narrow slots, all point to using a knife or fork, which can result in electrocution

p.165

When there is a problem, people are apt to focus on it to the exclusion of other factors.  The designer must design for the problem case, making other factors more salient, or easier to get to, or perhaps less necessary

p.169

Whoever invented that mirror image nonsense should be forced to take a shower.  Yes, there is some logic to it.  To be a bit fair to the inventor of the scheme, it does work reasonably well as long as you always use the faucets by placing both hands on them at the same time, adjusting both controls simultaneously.  It fails miserably, however, when one hand is used to alternate between the two controls.  Then you cannot remember which direction does what.

p.175

Each new set of features adds immeasurably to the size and complexity of the system.  More and more things have to be made invisible, in violation of all the principles of design.  No constraints, no affordances; invisible, arbitrary mappings.  And all because the users have demanded features.

p.183

One important method of making systems easier to learn and to use is to make them  explorable, to encourage the user to experiment and learn the possibilities through active exploration

p.188

Design should

The principles of design are straightforward

Design should make use of the natural properties of people and of the world:: it should exploit natural relationships and natural constraints.  As much as possible, it should operate without instructions or labels.  Any necessary instruction or training should be needed only once; with each explanation the person should be able to say, “Of course”, or “Yes, I see”.  A simple explanation will suffice if there is reason to the design, if everything has its place and its function, and if the outcomes of actions are visible.

p.209

Actually, increasing the number of controls can both enhance and detract from ease of use.  The more controls, the more complex things look and the more the user must learn about it. It becomes harder to find the appropriate control at the appropriate time.  On the other hand, as the number of controls increases up to the number of functions, there can be a better map between controls and functions, making things easier to use.  So the number of controls and complexity is really a tradeoff between two opposing factors.

p.216

Good design exploits constraints so that the user feels as if there is only one possible thing to do - the right thing, of course.

In the consumer economy taste is not the criterion in the marketing of expensive food or drinks, usability is not the primary criterion in the marketing of home and office appliances.  We are surrounded with objects of desire, not objects of use.