True but we know there are those days where you are rolling four D6's dice and you can't roll a 5 or 6 at all and 4's don't want to roll either.
You will end up with a character who is most likely going to die a horrible death.
As for my old "1" hit point Mage he did get to see the beginning of many of adventures and I knew that he was most likely going to die.
So he was fun to have as a NPC since if he was lucky he would get to cast his Magic Missile off and then die.
Take 1st Edition AD&D the chances of you rolling good enough to create a Paladin was not likely to happen (you need to have at least one roll that has two "6's").
But with a point system the player can ensure on getting that 17/18 point ability and still have enough points left over to get a couple of 13's and make sure that you lowest value is only a 10.
So like:
17 = 15 Points
13 = 5 Points (Total 20 Points spent)
13 = 5 Points (Total 25 Points spent)
11 = 3 Points (Total 28 Points spent)
10 = 2 Points (Total 30 Points spent)
10 = 2 Point (Total 32 Points)
Meets the requirements and still be a decent but not overpowering character.
But if you go with just rolling people will more than likely end up cheating.
Now take 5th Edition D&D they give you two ways to create a character:
First – is roll 4 D6's and remove the lowest die roll this should give you an average of around 12-14 for each ability.
Second – is that you are given 27 points to spend (using the above point spread) though the highest value you can have is a "15", so no 16, 17 or 18 stat scores.
Now in 5th Edition certain races get additional stat increases for certain stats.
Like Humans get a +1 in each of the stats, which is a very big incentive to create a Human Character.
Oh and has for hit points you start with max of whatever die you have for hit points and to lowest die is a D6 for a wizard, then adding your Constitution stat modifier.
So first level Wizard would have 6 + Constitution Modifier. Oh and when you gain a level you can either roll your hit dice of take a set value.
For a Wizard that set value is "4", while a Warlock who has a D8 set value is a "5" and a Barbarian who has a D12 value is "7".
Given this a Wizard character is more likely to take that set value instead of rolling while a Barbarian is more likely to take the chance and roll that D12 since the chances of getting higher than a 7 is worth it.