Crash325; My pet peeve is people that will give the same command repeatedly, to get the required results. If the dog doesn't know the command, because you haven't taught it, repeating doesn't help.
If the dog refuses the command, then one needs to make sure the dog does it anyway. Some dogs are very soft, so abuse is not necessary, even if a correction is.
If one continues to just repeat the command, it comes out as jibberish to the dog, and also teaches them that the first command really doesn't count.
Dog training can be a fun challenge, and I don't think I've ever seen a dog that didn't enjoy learning. Each is an individual, so one size of training doesn't fit all, but yelling is like repeating commands, it really doesn't accomplish much.
When I hear someone repeat "Sit" for the 10th time, and the dog is still not sitting, it drives me insane! Teach the command, gently, over time, then, when they KNOW it, give the command ONCE and make sure they do it! And, until you have a very reliable dog, DO NOT give a command that you can't enforce. Ever see people with a dog off leash, yelling for it to "come", and they have no way to enforce the command? So, all they did was teach the dog, that "come" is optional.
So much for being smarter than the dog!