Many people want the dog to fill up a spot of incompleteness in their lives. People may feel their child needs a companion or responsibility. Some people think that getting a dog will make them exercise more, as those dusty machines in the corner have not motivated them to do. For some a dog is a replacement for children they can't have or adult children that have left. Sometimes people think too much about what they dog will do for them, and do not consider what must be done for the dog OR the spirit in which care should be done.