I find it's easier to REDIRECT a behavior, rather than to STOP it, and it sounds like that is what Sekah is getting at too.
When you stop a behavior, you tell a dog not to do it. This sounds simple enough to us, but if the behavior is really rewarding (getting in the trash, pulling on the leash, etc) you are going to be fighting a losing battle with a stubborn dog.
If, however, you redirect that behavior into something else, something you approve of (and praise lavishly) most dogs will give up a previous behavior for a new, more rewarding one. (Just make sure your praise for the new behavior is on par with the reward of the previous behavior.)
For instance...
Dog gets in trash -> owner stops -> dog gets back in trash.
Why? Because trash is suuuuuuper yummy!!!
When you could have this...
Dog gets in trash -> owner calls dog from a short distance away (showing reward if necessary) -> dog comes -> dog gets treats/play time/praise, etc -> dog learns come is more rewarding than trash.
Or something like that,