Problems in Linear Sequential Model

The linear sequential model is one of the oldest and the most broadly used paradigm for software engineering. Criticisms of the paradigm have caused even active supporters to question its efficacy.  Between the problems which are sometimes encountered when the linear sequential model is applied are given below:

1.    The real projects rarely follow the sequential flow that the model proposes.  Even the linear model can accommodate iteration method it does so indirectly.  As per the result, changes can cause confusion as the project team proceeds.

2.    It is often hard for the customer to state all requirements explicitly.  The linear sequential model requires this and has difficulty accommodating the natural uncertainty that exists at the starting of various projects.

3.    The customer should have patience.  A working edition of the program will not be available until late in the project time span.  A major blunder if undetected until the working program is reviewed it can be disastrous.

4.    Developers are often delayed unnecessarily   in an interesting analysis of actual projects Bradac got that the linear nature of the classic life cycle leads to blocking states  in which some project team members have to wait for other members of the team to complete dependent tasks.  In real the times spent waiting can be exceed the time spent on productive work. The blocking states tend to be more prevalent at the starting and end of a linear sequential process.

Each of these problems is realistic. Moreover, the classic life cycle of paradigm has a definite and most important place in software engineering work.  It will give a template into which techniques for analysis, design, coding, testing, and maintenance can be placed. The classic life cycle remains the most broadly used process model for software engineering.   While it also does have weaknesses it is   significantly better than a haphazard approach to software development.