What you are actually deciding by making a will
Without a will, the Civil Code decides in fixed shares (legal devolution): with a spouse and children, one third to the spouse and two thirds to the children; without a spouse, everything to the children. A relative or an organisation you wanted to help does not exist.
A de facto spouse is not a legal heir, except in a parental union (in force since 30 June 2025 for spouses who became parents of the same child), where they receive one third. Outside that case, only a will lets them inherit.
A will also names the liquidator and a tutor for minor children. With no liquidator named, all the heirs act together and must agree at every step.
