Systems and methods for assessing drain pump performance in a washing machine appliance

A washing machine appliance, comprising:

• a cabinet;
• a wash tub mounted within the cabinet and configured for containing fluid during operation of the washing machine appliance;
• a wash basket rotatably mounted within the wash tub, the wash basket defining a wash chamber configured for receiving laundry articles;
• a spout configured for providing wash fluid to the wash tub;
• a camera mounted one of on or within the cabinet, the camera positioned and oriented with the wash basket within a field of vision of the camera;
• and
• a controller, the controller configured to:
• commence an operating cycle;
• send, during the operating cycle, an activation command to a drain pump of the washing machine appliance, the drain pump configured to drain wash liquid from the wash tub;
• obtain one or more images of the wash tub, after sending the activation command, using a camera mounted within the cabinet, the camera positioned and oriented with the wash basket within a field of vision of the camera;
• analyze the one or more images of the wash tub;
• and
• determine whether the drain pump is operating as expected based at least in part on the analysis of the one or more images, wherein the drain pump operating as expected comprises draining wash liquid from the wash tub at or above a minimum drain rate.