What incredible speed & movement ? Josh hit Usyk with his right while timing his head movement, Uasyk has a certain head movement pattern that Josh figured out, Josh didn't commit to his jab, he just used it as a range finder to see what Usyk would do, once he learned Usyk's pattern of movements, then Josh should've committed to his jabs but he continued to use it as a range finder this hurt his chances to win, the jab is the most important weapon in boxing without being confident to establish your power jabs you won't win a fight period, Josh never trusted his jab and fought cautious and this won't work he's bigger stronger longer but didn't utilize his strengths he fought down to Usyk's size fighting small.
You jab snap your opponents head back then throw combos head body, then use defensive movement boxing is easy when you establish your jab, this blinds your opponents temporarily and allows you to fire shots they don't see coming.
Usyk is a small slow heavyweight but his southpaw stance bothers certain fighters because they weren't taught the correct footwork aggression angles to get in punching range firing straight rights and body shots plus jabs they either can't pick this up or weren't taught everything, some trainer -s are limited in boxing knowledge, so Josh needs to get with others to learn the right techniques to beat southpaws, notice certain fighters have no trouble fighting southpaw fighters just watch Chavez Sr against southpaw fighters and Floyd against Zab, when he adjusted used constant smart pressure with straight rights body attacks and hooks with jabs watch his footwork, Floyd made it look easy but at first had serious trouble with Zab, even getting rocked hurt badly, if Floyd didn't make the correct adjustments he would've lost that fight because he's fighting a fight Josh did against Usyk, the same fight with the exact same results but Josh never adjusted, while Floyd adjusted and after that made everything look easy, Chavez Sr came out fighting the right fight against southpaw boxers like Camacho, fighting the exact same fight Floyd adjusted and fought against Zab, after looking the same way against Zab early like Josh looked against Usyk for 12 rounds.
Chavez uses the correct smart pressure head movement straight rights jabs not letting Camacho get set he's always off balance and on a definitive minded mode but getting hit with body shots jabs straight rights, others didn't do this and got beat by Camacho even older Ray, Whitaker is on a different level of defense and could adjust but others have done this to Whitaker although there's his cocaine issues so who knows, Whitaker still could be beat, Usyk isn't on Whitakers level of talent even Loma who's incredibly talented gifted isn't on Whitakers level of defense and footwork but Loma is very good.
Floyd was having the same trouble problems Josh had against Usyk, but Floyd made the adjustments otherwise he's losing the fight, just smart pressure correct footwork foot placement and keeping Zab off balance backing up while firing straight rights and body work nullified everything Zab could do, it's easy when you know what your doing, if you don't know how to take a southpaws advantages away they easily beat you, Josh never adjusted.