Why do people dump dogs here?

I’m absolutely disgusted by the people who dump the dogs and cats. Almost on a daily basis I see dogs in my neighborhood and in El Paso and I really don’t understand how you can do that it makes me sick to see that, just today my neighbor found an 6-8 week old puppy outside and almost had a heatstroke it literally breaks my heart . The dog above is the one that my neighbor found this morning now he is in a foster home