Hick's Law
Hick-Hyman Law, or Hick's Law, is named after a British and an American psychologist team of William Edmund Hick and Ray Hyman. In 1952, they examined the relationship between the number of stimuli present and an individual's reaction time to any given stimulus. What they found was that the more choices the users had, the longer it takes the user to make a decision. Users bombarded with choices have to take time to interpret and decide, giving them work they don't want. Today, designers call it KISS, or Keep It Simple
A good comparison is video games from 20 years ago. Video games were fun to play because they were so simple to learn. For example, Super Mario with just left, right and jump controls. In modern games, input controls are offering so many choices and combinations. All these controls, multiply the options user can choose in any certain situation. Having so many options makes learning the game and enjoying it much harder and time consuming.
A good comparison is video games from 20 years ago. Video games were fun to play because they were so simple to learn. For example, Super Mario with just left, right and jump controls. In modern games, input controls are offering so many choices and combinations. All these controls, multiply the options user can choose in any certain situation. Having so many options makes learning the game and enjoying it much harder and time consuming.
Use Hick's Law when response times are critical. It applies to any simple decision making with multiple options. This is especially important in control system environments. When things go wrong and alarms are blaring, users need to be able to make quick decisions. When users enter the stress zone they get tunnel vision. If we combine that with the input from all the body senses, we can get a pretty nasty situation. When response time is critical keep the choices to a minimum. It will speed up the decision making.
Hick's law can be used to narrow down large volumes of information without overloading the user. When we need to simplify complex process, we use Hick's law. Reduce the number of options on a given screen. Reducing the number of perceived options on screen makes the interface more user friendly. It is also more likely that the user will accomplish the goal and not give up or get confused. Breaking down choices to a series of too many small chunks can also cause the user to drop off before reaching the goal.
It's just as important to know when not to use it. Hick's Law does not apply to complex decision making. If decisions require extensive reading, researching, or extended deliberation. Hick's Law won't be able to predict the time to make a decision. For example, picking an AirBnB place to stay. Users need to consider and weight many options before making the final decision. In these cases, Hick’s Law prediction will fail. It only applies to simple quick decisions in appropriate context.
User's time is precious, don't allow bad design decisions to waste the user's time. Nobody is obligated to stay or use our app. Get to know the user, interact with them. Guide the user toward their goal by highlighting the choices they cares about. This will optimize the decision making and speed up the completion of the task. In the end, both sides will be happy.