Reports suggest that the cost of maintenance is high. A study on estimating software maintenance found that the cost of maintenance is as high as 67% of the cost of entire software process cycle.
On an average, the cost of software maintenance is more than 50% of all SDLC phases. There are various factors, which trigger maintenance cost go high, such as:
● The standard age of any software is considered up to 10 to 15 years.
● Older softwares, which were meant to work on slow machines with less memory and storage capacity cannot keep themselves challenging against newly coming enhanced softwares on modern hardware.
● As technology advances, it becomes costly to maintain old software.
● Most maintenance engineers are newbie and use trial and error method to rectify problem.
● Often, changes made can easily hurt the original structure of the software, making it hard for any subsequent changes.
● Changes are often left undocumented which may cause more conflicts in future.
● Structure of Software Program
● Programming Language
● Dependence on external environment
● Staff reliability and availability