You stay short as long as market goes down. At some point it will go up again. However, you never know when it is going to happen in advance. You can't know the price level or time period in advance. You never get out at the top or get out at the bottom.
Price action coupled with money management is key.
Once you have your price action bets ready to go you can't bet all of your money. If you have a trading signal and bet everything and lose all quickly, you are done. Money management keeps you in the game to play for tomorrow. More on technical indicator nonsense. It's useless, not to mention impossible.