Actually not mainly in trading or other forms of businesses but greed is mostly known in gambling. This is where it originated but later on adopted on other fields. We have several threads here about stop loss and each of users have their own different opinion in regards to it but I think, one thing is for sure and that is to identify your goals first. When you are done with that, that's the time you can tell if stop loss is really helpful for you or not.
If you have set your own goal, you must follow that no matter what, happens. So what if you see the price still flying? Just ignore it because it wasn't in your plan and you never know that it was only a trap. I am sure you don't want to lose more, than what you already earned.
stop loss is a good strategy to stop greed. because if you don't use stop loss, profits and losses will not be controlled. Greed will rule our minds when prices continue to rise and rise, no take profit is made if we don't use stop losses.
Some people have applied the rules well and the right strategy, but they even ruined all of that with their continued greed. this all depends on each individual. I will do the same with you to overcome this greed, which is to identify the initial goal first so that you know what to do and what to keep.