The idea behind a stop-loss is to not let losses of one of your trades get so big that it causes a significant drawdown in your overall portfolio.
The more efficient way is to trade with much lesser value. So when you are buying a stock, allocate only a small % of your overall portfolio to that trade. By doing this you can avoid putting a tight stoploss in place. The issue with markets is that they are hardly ever trending one direction, it is usually up and down even when they are trending one way. A tight stoploss means you keep getting chopped out.
If you put say more than 25% of your capital in one trade, you will be forced to put a tight stop as losses will mean a significant dent to your overall trading capital. This idea of tight stop-loss is usually peddled by tipsters to cover their ass when they are wrong. So that they can somehow prove that their tips overall made money. If you have really tight stops it is very tough to make money trading the markets.
How do you know if you have a tight stop?
If you are getting stopped out quite often, that means it is a tight stop.
About getting into the same stock after a stop has been hit. Yes, you can if your trading strategy asks you to. But don’t it for revenge and wanting to recover the money you have lost on that stock. Those trades hardly ever workout okay.