The iPhone 4’s antenna problems stem from its design: The antenna is that wrap-around stainless steel band and the break you see in the band. When a user’s big, hairy fingers bridge this feed point, the antenna stops working properly. An add-on insulating rubber bumper solves the problem by preventing the gap from being bridged. The argument that Apple is no worse than other manufacturers has to be one of the dumbest marketing positions ever. If something doesn’t work and it hasn’t hurt you somehow, what do you do? You take it back and get a refund.”]
Source: https://www.csoonline.com/article/2125490/the-iphone-4–just-take-it-back.html