I know it may still be too early to tell, as the sport is still
evolving, but (in my opinion), some UFC records will stand forever?
Or at least in our generation or pending some major rule change.
These are the current UFC records:
Consecutive wins (all active): 9 (Anderson Silva), 7 (Thiago Alves), 7 (Machida)
UFC fights: 22 (Liddell), 19 (Randy Couture), 15 (Rich Franklin)
Title wins: 9 (Matt Hughes), 9 (Randy) 6 (Anderson Silva), 5 (GSP)
Consecutive Title defenses (active): 5 (Anderson Silva)
Title fights: 15 (Randy)
Fastest KO: 8 secs (Don Frye vs Thomas Ramirez, James Irvin vs Houston Alexander)
Fastest sub: 16 secs (Marcus Aurelio)
Most KO wins: 10 (Liddell), 8 (Rich Franklin), 7, (Thiago Alves)
Most sub wins:: 11 (Royce Gracie), 5 (Demian Maia), 4 (Dustin Hazelett)
Oldest UFC fighter: 51 (Ron Van Cleif at UFC 4 vs Royce Gracie)
Youngest UFC fighter: 18 (Dan Lauzon at UFC 64)
So all the current streaks, especially the active ones could obviously be broken.
The 15 Title fights by Randy will be unbroken. At one point, he had 9 straight title fights.
The fastest KO record has been broke, but it was outside of the UFC and if it could happen outside the UFC, it can happen inside. Kid Yamamoto flying knee'd Kazuyuki Miyata in a K-1 fight in 4 seconds.
Fastest sub will stand. In that 16 seconds, both fighters touched gloves, threw some "feeling out" jabs, a little dancing around, and then Aurelio rocked Ryan Roberts to the ground with a punch, proceeded to secure his back while throwing punches to the face. Once Roberts tried to roll out of it, Aureilo grabbed the arm and armbarred him. He actually tapped out at 14 seconds but the offical was 16.
Most subs can possibly be broken by Maia.
Dan Lauzon's record will be broken some day. Fighters are always starting younger and someone younger is bound to start earlier, by days, weeks, or months, not sure if you can fight in the UFC at 17.
And Van Cleif will always have his record.