Well, don't all character have a base chance to resist stun effects? Like 5% or something? I'm not too sure, but I see my KS resisted by classes that don't have talents I think sometimes.
Otherwise, HoJ being a spell, and most Rogues being Hemo with the -4% hit to spells cast on self, if you don't have any +Hit with spells it's 8% with the 4% base chance in PvP, iirc.
Add on top of that the "natural" stun resist if it exists, and yeah it begins to be somewhat frequent to get a resist, and then you got classes with more powerful anti stun talents (Priest, Warriors) and those fucking Orcs

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