Have you ever noticed that a dog's sense of time is limited to "forever"?
When you leave for work, they mope.
"Aw crap. He's NEVER coming back. I'm gonna die.
When you arrive home from work, they are ecstatic.
"Oh boy, Oh boy, Oh boy, Oh boy, Oh boy, Oh boy, Oh boy, Where've you been!? Where've you been!? Where've you been!? Where've you been!? I thought you'd NEVER come back!!! Pet me, pet me, pet me!!!!"
A dog’s sense of time is a little more complex than that. A year is seven dog years, and if you do the math, that means that a dog minute is about 8 or 9 seconds.
So, if you tell your dog to ‘wait a minute’, and about 8 or 9 seconds later he’s begging AGAIN, don’t yell at him - he waited a minute.