How to prevent slips in UX design

Slips is some action that users make unconsciously. For example if user press one button instead an other on keyboard. Or press "close" instead of "save". Slip can be made by experienced users as well as new one. Designers must prevent slips.

If some user can do wrong action and the system know that it is wrong - a designer has to disable this action. A return flight is always later than a departure. So previous dates might be disabled to prevent their selection. Users can free their memory from unnecessary information.

Many slips come with inaccurate typing. A mobile keyboard is too small and users often press other button. An interface might show clickable search suggestions to users. Such as list of potential destinations on this page. It is good example of "low calorie" design - users are thankful because they have to type less.

Some websites are so smart that can recognize a slip and give users right suggestions.

Users might forget to fill some fields. It is also a slip because they know how to do right but did wrong. Designers can make users experience easy if they put some reasonable defaults.











On this on-line marketing tool the start date and campaign name are filled by default when user just create new one. So there is no need to show error message.

Users make often mistakes in an important fields like phone or credit card numbers. A designer can make this data easy to check by formating. Modern JavaScript technology can format the users’ input as they type.

It is very hard to check 16 digits in-line. So a credit card number is splitted by spaces usually .

If the field is very important (like email, or password) the slip can be critical fault. Conformation of these fields are necessary part of slip prevention.



A designer have to give users an opportunity to fix their slips. Have a look at these messengers.

Users cannot edit a message in Line messenger.

Users can delete a message in facebook messenger.

Users can edit the last message in Skype. It is very good UX to fix slip problem.




Summary
Slips are often errors of all types of users - new and experienced. Designers have to prevent slips with good design, such as:
1) Disable wrong actions.
2) Make suggestions to users.
3) Use default value of fields if it is possible.
4) Give users tool to check their information or ask for confirmation.
5) Give users opportunity to fix a slip.