Bonding is called "Bonding" because it is DENTIST-MADE and BONDED in at the time of appointment. A Veneer is LAB-MADE and CEMENTED in multiple visits, usually. Less lab work lessens the cost. However, there is always a tradeoff. Bonding is essentially the same material used for tooth-colored fillings. Therefore, they chip and break more easily than a veneer that is cemented on.  Bonding may also break a larger portion of the tooth the second time it fractures, leading to something more costly dental treatment (e.g. Root Canal or Extraction / Dental Implant)