You see its mouth? Does it have a secret carnivorous diet? Maybe it eats meat when you’re not looking? Maybe it wants to attack you even when you don’t provoke it but it tries not to?
Me at level 24: I tamed an ankylosaur, this should be easy. Five minutes later :HOW ARE YOU NOT ASLEEP, I shot you with Tranq arrows like ten times, I REGRET MY DECISION!!!!!!