Well if your asking and asking and asking... and if the horse isn't listening to you and your not sure when to actually smack him on the butt.... sometimes and extra "HEY LISTEN!" from the ground helps with making sure your safe in the future
Horses arn't all pink flowers and unicorns.... the wild west wasn't won by 'soft' people.... horses are big animals and in order for people to be safe around them you need to make sure they have your horse's attention and know your the leader.
Smaller animals... like dogs... are much easier to read partly because they want to please you all the time. Yes there are many horses out there that want please you also... but horses tend to have a huge lazy side of not wanting to work. And when that lazyness comes out its easy to lose your horse's attention since they will learn that your much smaller then they are.