Critically appraise the role of the project manager with in systems or software development projects.

I have some questoin about project management !Nowadays ,Some in the computing industry argue that software projects have such a poor performance in success rates, against other industries that it must be because of poor professionalism in the industries, the problem is that we expect more from software projects than traditional engineering projects.Can your existing knowledge of project management from the software and information technology related areas, expand your knowledge through further reading and then discussing the above statement.

Thanks you!