

Nothing needs to go up. Shorting stocks lets you make money off of them when they go down. If a person or group of people can cause a crash and know in advance what day it’s happening, they can borrow stocks and then buy the stock to repay the loan at a lower price and pocket the change.
Try wrapping it in aluminum foil. You can test to see if it works by trying to call your phone from another phone while it’s wrapped up.