How does the number of defects remaining in a program at the time of delivery affect product support:
No program is defect-free and it is not necessary for a program to be completely free of defects before it is delivered to its customers.
That said, the number of defects remaining in a program at the time of delivery can affect product support positively if the defects are known and well documented. Proper identification and documentation of defects will make it easy for the support team to investigate and escalate the defect to the development team.
However, when a defect is unknown, or known but not documented at the time delivery, a lot of time will be spent investigating the defects. After product delivery, the support team will need to work hard to uncover and document them quickly, before escalating the issues to the development team.
Early detection and documentation of defects goes a long way in making the work of the product support team more efficient and effective. The development team are also affected similarly since they rely on the support team for information regarding product defects.