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:

Real-world factors affecting Maintenance Cost:

• The standard age of any software is considered up to 10 to 15 years.

• Older software's, which were meant to work on slow machines with less memory and storage capacity cannot keep themselves challenging against newly coming enhanced software's 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.

Software-end factors affecting Maintenance Cost:

• Structure of Software Program

• Programming Language

• Dependence on external environment

• Staff reliability and availability