For some reason, people in Colorado do not understand the concept of picking up dog poop.

Every few weeks, we get photos showing piles of dog waste, picked up and bagged by volunteers, all because dog owners somehow decided it wasn't worth picking up. Or hear about a dog park that is closed because there is too much crap in it. Or even a stream contaminated with E.Coli due to leftover poo.

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We wanted to know if there is a psychological reason people leave behind dog poop.

So we brought in Dr. Max Wachtel who discussed the reasons some people don't pick up after their dog with Steve Staeger.

He says one reason is simply because poop is gross and some people may have more a problem picking it up than others.

He also said that it's easier for people to make a commitment in the future than right now. They may originally say that they intend to come back later or pick it up on their way to the car, but then never get around to it.

But, overall he says it comes down to simply being a responsible pet owner.