It's not a matter of not challenging yourself - it's a matter of challenging yourself with the resolution of the unknown and not with spending weeks trying to learn the skills you'll need just to analyze the problem. Revise to fit within you logistic limitations. You have a limited amount of time and money. Make sure that it is feasible for you to undertake your study. In my experience, the number one project killer of all time is over extension.
Problems have a way of blowing way out of proportion.
Select a simple, clear statement that you have the time and budget to attack. However, having a thesis or other investigation accepted as is, and, then struggling to cover all the bases is a frustrating experience. 5. Definitions. Make sure that every phrase and word within your problem statement is either painfully clear and obvious or clearly defined. You don't necessarily have to put it in the problem statement itself, but the words must be both clear to you and to anyone who will review your project. This sounds obvious, but it isn't.