Every system has an amount of complexity that cannot be removed, only moved.
Decide who carries the complexity. Move it from the person using the product into the product, where the team solves it once.
Larry Tesler, a computer scientist who worked at Xerox PARC and later at Apple, is credited with the idea, which is also called the law of conservation of complexity. While working at Xerox PARC in the mid-1980s he argued that every application has an inherent amount of complexity that cannot be removed or hidden. The only question is who deals with it: the team that builds the product or the person who uses it. Tesler is also known for helping to bring cut, copy and paste into everyday software.
A delivery form asks for street, city, state, postcode and country in five separate boxes. Someone has to work out the full address either way. In version one, the customer does it, typing every part and fixing the typos. In version two, the customer types the first few characters of the street, picks the full address from a list, and the form fills in the rest. The address is exactly as complicated as before. The difference is who deals with it: the team that built the lookup, once, instead of every customer, every time.
Do not absorb complexity when the person needs to understand or control it. A tax form, a medical consent or a privacy setting should not be filled in silently for the user. Sometimes the right answer is to show the complexity plainly, in small steps. Tesler's Law is also not a reason to ship a complicated product. It says complexity has to go somewhere, not that you should stop removing the part that is not essential.
Pick one task and count the fields, choices and rules the person has to handle. For each one, ask if the system could work it out. If it could, it is your job, not theirs.
Tesler's Law, also called the law of conservation of complexity, says every system has an amount of complexity that cannot be removed. It can only be moved, either onto the people who build the product or onto the people who use it.
A computer scientist who worked at Xerox PARC and Apple. He is credited with this law and is known for helping bring cut, copy and paste into everyday software.
An address form that suggests full addresses as you type. The address is just as complicated as before, but the system deals with it instead of the customer, who picks one line from a list.
Decide what the person must choose and what the system can work out, then move the second group into the product with defaults, lookups, detection and pre-filling. Let people check and change what was filled in.
No. It means you should be clear about where the complexity goes. Remove what is not essential, and for what is essential, make the product carry the load instead of the user.
A delivery form asks customers to type their street, city, state, postcode and country into five separate fields. Many people mistype the postcode or pick the wrong state, and orders arrive late or not at all.