“by the numbers” is a phrase used to describe a Set path or a script so to say.
And you answer it yourslef. D3 vanilla had no build defining items, so you had total freedom what to pick and the only important thing has been the raw power of the items.
In D4 you follow a certain path. The path of your build. The items are pretty much predetermined except a few freedoms maybe.
It becomes worse when you wanna play a Build that does not have a “by the numbers” script, because then you lack an insane amount of Dmg no matter how powerful your items are. This is the worsed part. You can have total insane items with 12/12 super and still get outperformed by a beginner char that uses a meta build.
Now that i think about it it realy bothers me how anyone can think the D4 and D3RoS system is any good. The game is laying out a path and yojust follow it all while they make you believe you “play your way”.
I never felt like d4 let’s me play my way…