Most garbage speakers I have seen (and heard) had 3 things in common: Cheap connectors, a little tab to pull off the velcro attached front grille, and a frequency response graph showing flat response from 30Hz to 22kHz.
Should Speaker Manufactures provide a Frequency Response Graph?
Eric at Tekton Designs has been battling two different reviewers who have posted measurements without his permission, using Klippel devices for their respective measurements.
It seems to me that if manufactures provide a simple smoothed out graph, consumers can see how much a speaker is editorializing with a frequency response that deviates from neutral.