We need to pull up the stats on that. I've seen it said the one who misses weight tends to win, likely as they give up before the hardest last part of the cut that their opponent goes through.
Obviously, it's case by case. Ortega did look like a wreck.
In
42 UFC bouts from June 2016 (when early weigh-ins began) through early 2018, the fighter who missed weight went 23-19 (54.8% win rate).
In a larger sample of 63 UFC bouts (combining pre- and post-early weigh-in eras up to early 2018), the fighter who missed weight went 31-32 (49.2% win rate, essentially even).
In a
general analysis of 5,719 professional MMA bouts (not UFC-specific) where one fighter was 1.75-6 pounds heavier, the heavier fighter won 54.6% of the time; this rose to 55.1% for 1.25-5 pound differences.
In
2021, fighters who missed weight went 14-13 (51.9% win rate).
There are a few more variables according to the MMA Fighting article:
Favorites vs. underdogs: Favorites who miss weight win at higher rates (e.g., 76% in the 2016-2018 sample), while underdogs who miss win at lower rates (e.g., 33%). Underdogs are more likely to miss weight overall (about 56% of cases).
Amount missed: Missing by 4+ pounds yields a 44% win rate (8-10 record), and missing by 6+ pounds is 0-4. Extreme misses (7+ pounds) always result in losses in modern UFC data.
The slight advantage for the weight-misser is often attributed to retaining more size/strength on fight night without a full cut, though a botched cut can lead to fatigue or other detriments, as was mentioned by
@MMAfan4life2
