FRST is an advanced specialized tool created by Farbar, a Security Developer who has also created a number of other tools used by malware removal experts. FRST is primarily designed to run in the Windows Recovery Environment via Advanced Boot Options or by using a Windows DVD in order to diagnose and fix boot problems or remove malware when other tools fail. It can also be used in Windows XP if the system can boot to PE Environment by using a Boot CD and can also run in normal or safe mode when logged in as a user account with administrative privileges. FRST logs provide detailed information about registry loading points, services, driver services, Netsvcs entries, known DLLs, drives, and partition specifications and will also list system files that could be patched by malware.
I have another question. Is it better to scan system monthly with FRST or Malwarebytes free is enough?
FRST was never meant to be used as a general purpose malware scanner like Malwarebytes, Zemana AntiMalware, SuperAntispyware, AdwCleaner, etc which scan individual drives, different folders, the registry, etc on a computer for malware.