Amitosh Swain wrote:

the operations that perform on the selected object may not check for null values(stupid, viewmodels and moron designers!) and hence poof!, a crash.

If you attempt to fix this problem by removing nulls you'll find you still have a problem with your program; it'll be displaying and\or using incorrect data. Removing nulls won't fix the root cause of your problems, it will just change its nature, and since the nature of problems using nulls is a crash or exception, bugs which are very easy to trace and fix, i don't know why you'd want to change it.

My personal favorite, encountered only once while trying to open a project file in Borland C++Builder 6, it went something like; "We were unable to process your request. Reason: The window does not have scroll bars." Yup, apparently scroll bars are an essential part of loading the file.