Project size and Project Risk: Another interesting topic in Project Management world. From my experience with software development, I think that project risk increases with the size of the project (I guess the size of the product would be directly proportional to the project size). Here is the reason -
Consider that software product consists of 25 modules. The following is a fact -
1. Not all risk associated with a software module or functionality is identified by even very efficient Risk Analysis methods.
2. Presence of residual risks
3. Presence of secondary risks
Given above situation, if we increase the software size, by say, 25 modules (totaling up to 50), the risk would be doubled. In other words, project risk is directly proportional to project size.
The various aspects of project size (software projects that I am familiar with) that drives project's risks are size of the software product in terms of programs, modules, interfaces, db transactions etc, number of database tables/databases, number of users who would use the software, project scope changes and project communication.
Is it possible to have a large project with low risk of failure?
Yes, absolutely - A large project can have low risk of failure, provided we use efficient Risk Management techniques.
I have been part of a few software development projects, which were quite large in size and were successful. Example would be the E-Governance project (I have been citing this project (http://www.maharashtra.gov.in/) in many of postings in order to correlate and understand various subject matter) that I have handled in my previous job. The project size was quite big encompassing the official government website and related applications, in-house content management solution and about 8 different intranet applications which is used by over 7000 employees every day. The total project phases took 2 years to implement and test run the system. The project was successfully implemented and risks were managed effectively to the point that state government won the national golden award for best e-Governance initiatives (http://www.maharashtra.gov.in/award/goiAward.php). The user (state government) still sees the project as one of its major success and traces it back to the success of the project team (software company and in-house players).
Is it possible to have a small project with high risk of failure?
Yes, absolutely - A small project can have high risk of failure if there are project risks un-handled.
Consider the case of a project which has scarce expert resources. If the company doesn't pay attention to appropriate employee retention policies and if they do not plan risk response and contingency resources in case any of these employees switches company, this would open avenue for project failure.