There are many factors which decide how a scar would look like. Some of them are
It should be noted that a scar can not be completely removed even by plastic surgery. A plastic surgeon tries to make the scar less noticeable with the help of various techniques. One of them is the procedure of scar revision, an operation for making the scar less visible.
Most scars settle over a period of one year, that is they become less visible, less hard and symptoms like itching and redness decrease. Hence plastic surgeons advise to wait for about a year after injury or operation before going for scar revision surgery.