The Cost of Maintenance คา่ใช้จา่ยของการบ ารงุรักษาระบบสารสนเทศ ขนึ้กบัปัจจัย ดงันี้ • ขอ้บกพรอ่งแฝง(Latent defects): This is the number of unknown errors existing in the system after it is installed. • Number of customers for a given system: In general, the greater the number of customers, the greater the maintenance costs. • Quality of system documentation: makes it easier to find code that needs to be changed and to understand how the code needs to be changed.