1. A method of improving performance of video analytics for a camera system in response to a detection preference of a system user, comprising: while the camera system is already in in-field use, receiving image data representing multiple images of a scene of a field of view of the camera system, the multiple images including representations of multiple objects, a first set of the multiple objects having members of an object class, and a second set of the multiple objects not having members of the object class; while the camera system is already in in-field use, using video analytics implemented with a general classifier that performs general classifier steps in analyzing the received image data to produce a general classification determination classifying the multiple objects as either members or non-members of the object class; while the camera system is already in in-field use, generating mistake metadata in response to acknowledgement by the system user that the general classification determination resulted in a mistaken classification determination based on the detection preference of the system user; and while the camera system is already in in-field use, improving video analytics performance based on the mistake metadata by performing a specialization step in addition to the general classification steps performed, the specialization step producing for presentation to the system user a specialized classification determination of the multiple objects classified by the general classifier so as to reduce a number of future mistaken classification determinations.