Round faces are different from chubby faces and differ in the facial features also. Basic geometry of the two kinds differs vastly from one another. A round face would have the perfect round shape with the length and the width of the face reading the same size while a chubby face might have extra cheek fat or extra fat due to body fat. Oval face shapes are the ones that would go with any kind of hairstyle. So one has to be very careful in choosing short hairstyles for round faces, as a wrong choice would make the face look more round and chubby.
No matter what hairstyle you choose, it is important for the hairstyle to not only fit your facial shape and skin tone, but it must fit your personality too. In spite of the fact that hair grows out, you have to be comfortable with the style from the beginning. Most of us do not have the luxury of calling our employer and saying "I'm not coming to work for the next few weeks because I don't like my new haircut." Probably more than any other hairstyle, short hair takes courage because if you don't like it, other than a wig, there is nothing you can do about it. You must be patient and wait for Mother Nature to change the length.