ProfessionalPwn3r

Hey all ! Greetings.! This is my 1st thread I have just a quick question regarding CTFs or Linux Systems. Anyone up for clarifying my doubt? So almost any CTF machine without GRUB or Kernel restriction can be easily tweaked to gain root access.! If so, i think this can be a legit way to enter the system and perform rest of the activities.It saves time and doesn't require privilege escalation exploits. If not, please do tell me why this can't be a legit way?