God can't save us if no stop loss

Exactly.
Sometimes you don’t need SL for scalping, but it is always better to set on than never

Right, SL is like a barrier against major losses, even I try to incorporate it in most of my strategies.

Stop loss is mandatory.

I could have not agreed more to that, I make sure to be very firm with the stop loss, whenever I am trading. I strongly believe that at times, it is important to resuce the losses instaed of making profits.