It's the lack of curiosity in not taking the small extra mental step of thinking "what niche does this clearly physically different product address?" that's the most galling/disappointing. Or having done the search and found very cheap alternatives thinking, "clearly the person setting up a business creating and with a partner that using these products daily missed that this already exists" immediately instead of looking at why JerryRigEverything might not be an idiot wasting his money.