I guess it depends on the country and how much the will deviates from reasonable clauses? I’m looking into making one now, and a notarised will has to have rea

I guess it depends on the country and how much the will deviates from reasonable clauses? I’m looking into making one now, and a notarised will has to have reasonable clauses straight away; an enclosed will that is open later can say whatever you want, but might be contested if it’s unreasonable.