For each field, you can define a minimum confidence value to govern the accepted results from a locator.
A locator typically returns several items that match the locator definitions. These are called alternatives. Each alternative is evaluated and assigned a confidence value by the locator. Alternatives that do not meet the minimum threshold are ignored. The locator then selects the best of the remaining alternatives and stores that value in the field.
You can also define threshold values to determine whether a field is valid or not. The field is given an invalid state if the confidence value is lower than the minimum confidence threshold or if the distance to the second best alternative is less than the minimum distance.
For example, when using the default threshold values, the best result has a confidence value of 81% and the next best alternative has a confidence value of 75%. The best result is not confident, even though it meets the minimum confidence value. Since the minimum distance is set to 10%, the next best alternative needs to have a confidence value of less than 71% before the best result is accepted as confident.