I think when riding horses, there is an order in which you should achieve what you want from your horse.
Step one : ask nicely. Say you park your car in the wrong place. And someone comes in and starts yelling at you to move it. Wouldn't you rather if they came in and nicely asked you to move it? Rather than just jumping to screaming at you?
Step two : AFTER you have asked nicely, ask with a little pressure. I really don't have a good metaphor to give you here.
Step three : tell them what you want them to do and don't take no for a chance.
I know many horses that if you spur them, they won't go, but if you just ask with your voice commands and a small squeeze, they will go no problem.
In your relationship with your horse, you expect to be respected by them. You expect them to look to you as the boss. However, you cannot expect to receive respect if you don't give respect.
So always keep in mind that its best to start nicely, respectfully, and add more 'umph' when they don't listen to you.