Simps, yes, I was thinking the exact same thing when I got the response.
Reasons for ineffectiveness(at a minimum):? Obese person with deep tissue injury
Bone bruise or Musculoskeletal Pain
Didn't turn on....yes it happens
Not positioned properly
Didn't leave on long enough
Defective device
Elderly, unable to work device
Etc, Etc, Etc.......
Anytime your dealing with human consumers, there will be a percent of error or ineffectiveness, whether your reading a review on amazon or a clinical trial, there will always be a sample of non-positives/negative responses. It's the human nature deficiency. :-).
Bottom line is that we know it is an extremely effective device...we just need to get the dam thing out on the street BIGLY!!
All IMHO
Take Care......have a good week-end