>>45908196>Max moves are not nearly as strong as Z moves on base power.They do more damage over the 3 turns than Z-Moves, but the takeaway for Max Moves is they're not strong enough to compensate for the buff in HP
>252 SpA Life Orb Greninja-Ash Max Geyser vs. 252 HP / 128+ SpD Dynamax Heatran: 515-608 (66.7 - 78.7%) -- guaranteed 2HKO after Leftovers recovery>252 SpA Life Orb Greninja-Ash Max Quake vs. 252 HP / 128+ SpD Dynamax Heatran: 640-754 (82.9 - 97.6%) -- guaranteed 2HKO after Leftovers recoveryDynamax overwhelmingly favors bulky offense or fat mons. 80 BP moves (that give 30% status in base form) get the most dramatic max move buff, and offensive Pokemon can't break these mons even with super effective moves.
This is why in Ubers, Yveltal and Necrozma-DM are the best dynamaxers, as they're extremely bulky and have drawback-free dynamax STAB moves that get the highest BP increase.