I'll say this about that
ABSOLUTELY NOTHING, that is NO THING works like it does on TV.
But by the time you find that out, you don't care to send it back and they've made their money.
They oversell it and you say "well if it's only half that good, it's worth it. " So you buy one super ultra widget (SUW) and it's GUARANTEED!
Now you discover that the SUW all neat and shiney, but it don't do nothing like they song-and-danced it would. So you think about sending SUW back, or maybe you SWEAR you'll send it back, and where is it NOW? Oh, it's out there in the laundry/garage/shed/carport/basement on a shelf next to the other whizzamaccallit you bought last year. Sure, some get sent back, but not enough to hurt the profits involved.
And where are the INFOMERCIAL people--watching the sunset in a warm sandy place, having drinks prepared by other people... and us shrewd consumers put them there.
The very old rule applies here: If it sounds too good to be true, it probably is.
And the INFOMERCIAL rule: If you tell a big enough lie, loud enough and long enough, people will begin to believe it, no matter how absurd.