A good taper will know precisely when to use a wider or thicker tape roll, when to double the roll, and exactly where to apply a little more plaster in order to strengthen the tape. Taping should be very simple, and will make the wall look completely uniform. A wall may look perfect at the end of a paint job, but a year or two later the seems will begin to open and will be made visible. Just like every other part of a renovation, taping requires skill and experience. As a consumer you should always make sure that your taper does a good job and does not cut corners.