I don’t think “the decisive moment” is the most accurate description in street photography. The notion of the “brazen” (daring, gutsy) moment seems more fitting.
There are so many moments we witness that we want to photograph but fear and hesitation prevents us. This is why in these moments, we must be BRAZEN and ballsy to shoot the moment, even though we might get verbally (or physically) abused.
Adrenaline is good.
How do you know if a moment might be good? Follow your adrenaline. If while you’re shooting a scene and you get an adrenaline rush, then it is good!
Daring photos are more fun.
Just because it is scary or difficult to shoot a certain scene doesn’t mean it is a good photo. But when you’re more daring in your photography, it is certainly more fun and interesting!
Shoot what scares you.
Photograph more brazen and bold scenes. Discomfort is good unto growth.