You might think, "Why can’t they just start at 7 PM so I can go to bed before my alarm clock turns into a monster?" The answer is money, but also vengeance. Promoters know that if they make you wait until your eyelids are taped open with caffeine, you’ll buy more overpriced PPVs and sign up for streaming services you’ll forget to cancel until 2026.
There’s also the "American Factor." If the fight is in the US, the UK time is 5 AM, which is a time zone reserved for milkmen and existential dread. So, they schedule it so we can watch it over a late-night snack of regret. This ensures that every UK viewer has the shared trauma of falling asleep during the undercard and waking up to a man in a shiny robe saying, "And the new…" over your cat’s head.