For home use this is not as much of a problem as a frustration.  Just reinstall the program.  But in a corporate network this creates a problem with company distributed installs and updates, it is difficult and time consuming to know who has a broken install and who does not.

In a corporate network software distribution installs and OS patching can fail if an employee responds incorrectly to a prompt from a active monitoring security product.  When used alone (as an active monitor) Repelit stops user error and prevents broken program installs.