Getting the right puppy is very important. you have to make sure that it will fit in with your family and yourself. If there are small children in the house the puppy has to have the kind of nature that won't mind having it's tail pulled every so often.
And, if you are a little older and live alone you have to make sure that the puppy doesn't need to have a lot of exercise if you can't run with it.
Plus, you have to make sure that you love the puppy as much and the puppy loves you. The saddest thing is to see a dog returned or worse, left in the street, because the owners couldn't care for it.