These are usually anti-spyware or security software applications that use various forms of deception and/or unethical means or show a history of negligent false positives to goad the end user to make a purchase.
In some cases these applications maybe downloaded with some form of unwanted software at which point the rogue application is offered to the customer as a way to remove the unwanted software.
Spyware Soft Stop is a Rogue Anti-Spyware.
Spyware Soft Stop installs six rouge files that it then detects and falsely displays as spyware in the scan results seemingly to scare the user into paying for the application. These same six junk files are displayed as spyware with a different name in the next scan.
Files installed by Spyware Soft Stop. These files are then detected by the software to make user think they are infected.