37. The computer-implemented method of claim 36 , further comprising: determining that a particular quantity of training examples of the particular candidate hotword are available to the speech recognizer; and wherein determining that the particular candidate hotword satisfies one or more hotword suitability criteria comprises determining, based at least on the particular quantity of training examples, that the particular candidate hotword satisfies one or more hotword suitability criteria.
36. The computer-implemented method of claim 21 , wherein determining that subsequently received audio data includes sounds that are characteristic of an utterance of the custom hotword comprises: determining, using a speech recognizer, that subsequently received audio data includes sounds that are characteristic of an utterance of the custom hotword.