Top 5 VUI Dialog Design Guidelines for Handling Errors - #2 of 5
Posted by: eolvera, in Usability, Dialog DesignContinuing the series, here’s the second guideline for handling errors when designing Voice User Interfaces:
Guideline #2: Maximum of two errors - of any kind!
Most systems keep track of error events using individual counters for each error event (no speech and no match), which could potentially be reset if the interaction is part of a complex tasks that requires multiple interactions (e.g. A user validation that requires a combination of account number and password).
Therefore, it is possible that a caller would need to error more than two times before the system transfers the call to an operator (e.g. a no match followed by a no speech timeout), in some cases leading to infinite loops from which users cannot recover (e.g. user enters an account number and PIN which don’t match, so for security we ask them to reenter them again which in return resets individual error counters for each individual piece.)
In order to avoid that situation, custom counters should be implemented to account for cumulative errors that could encompass multiple error types, multiple states, or even multiple tasks in a single call.
For example, a system could be developed to only allow a total of two consecutive errors anywhere in an application (no matter the error type), two consecutive retries (e.g. validating a user, performing a money transfer, etc.), or a fixed number of total errors on a single call.
Other articles on this series: [1], [3], [4], [5] and [extra]