Consider the Intent, ‘WhenIsTheirBirthday’. You might provide utterances such as, ‘When is Jane’s Birthday’, ‘When is Bert’s Birthday’, etc. When you Test the phrases you might find a test that only results in a very low confidence score, e.g. ‘When is Tim’s Birthday’. Don’t be tempted to add that as an utterance, if you do you will be providing very specific training and you cannot be certain that your are really improving the model. In that example, you would just add some more utterances that are similar, but not the same, and re-train. Keep doing that and you should see, ‘When is Tim’s Birthday’ confidence start to rise until it goes above your required confidence level.