Remember, Dogs don’t know human language.  We have to teach it to them.

Rasta the Labrador Retriever is outside digging up the newly planted garden
You say. RASTA COME HERE! Rasta looks up at you and continues digging. So, you go over to Rasta grab him by the collar and yell. "I told you to come here," and give him a smack. Rasta, being the smart Lab he is, makes a note. Come here means I’m in trouble and I’m going to get smacked or punished. Next time he is outside and you want him to come in for dinner, you say. Come here. He responds by running the other way. Wow, dumb dog you think to yourself. So, you go get him and say. "Why don’t you come here when I tell you too." So, Rasta thinks to himself, yup my memory serves me right, "come here" means angry human.

The bottom line is this. Rasta needs to know that "Come" means get your little butt to me as fast as you can, always, no questions asked. So, we need to make Rasta understand that "Come" means Good Stuff!
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