Larian Studios Forums Divinity: Original Sin 2 Divinity - Original Sin 2 - General Why do we need primary attributes?

You need int to equip wands (ok, not that much) and dex (bow, crossbow, dagger) or str (sword, axe) for other weapons (highest requirement at lv21 was 16, at least in my game), so you have to raise the primary stats to equip things.

Raising your primary stat raises your damage and success chance. Each spell has a base stat and a base value. Each point below the base value lowers your damage/success chance by 10%, each point above the base value raises it by 5%.

Example 1: (arbitrary names and numbers)
Lets say you have a fireball spell based on int, the base value is 10 int and the base damage is 100.
If you have 9 int, damage will be 90. If you have 11 int, your damage will be 105.

Example 2: (arbitrary names and numbers)
You have a charm spell based on int, base value is 10 int and base success chance is 80% against an enemy without resistances. If your int is 9, your success chance is 70%. If your int is 11, your success chance is 85%.

Even buffs you cast on your party members can fail if your primary stat it too low.
You must also remember that raising the primary stat lowers the cooldown of many spells.

I see no reason not to focus on one primary stat and speed, though there may be other useful builds.

I admit that I finished the EE only once (Sorry, there are so many good games in the world). I did it with 4 chars that focussed on one primary stat and speed and the game was very easy once I passed level 6.
My fighter with high str, 5 points in dual wield and self crafted weapons killed every enemy in 1 or 2 hits.
My archer was very good in doing party friendly damage at any distance. Some special arrows are also nice.
My mage was very good in CCing most enemies.

summary:
It is easy to make a good char if you follow some simple rules. You can make very powerful chars (maybe even more powerful than the usual chars) if you know what you are doing and then ignore those simple rules.
But for new players who have little experiance in computer RPGs it is very easy to create a bad char.