There are many reports that ebay, and even amazon, are full of sellers that sell fake sd cards and usb sticks: These media report themselves as being e.g. 64gb, while actually only having e.g. 8gb of actual storage. Even worse, their microcontrollers are tampered such that they will actually fake accepting the data, and will even try to accommodate it, until they run out of space, at which point they simply dump the data.

Programs such as f3 (github) and others have algorithms to detect such drive, though the ones that are exhaustive take a lot of time. Some of the programs have heuristics, which may be a better fit for Etcher.

In an ideal world, we'd implement some heuristics that can detect if there's something "off" about the card, either ahead of time, or in the process of writing it. When we do, we can inform the user, and let them know what they can do.

Etcher is getting used very widely, this is an opportunity to make a real difference.