4e ability checks

[Matthew]

As opposed to 1ed where no one could really do anything due to the poorly thought out nature of nonweapon proficiencies. Hey, Mr. Fighter, save ALL of your NWPs until like 5th level if you want to be a Weaponsmith. You won't be a very good one, though, not like the Magic User, who could do it at first level and whose prime requisite is the defining attribute. Same goes for Rangers, Paladins, Cavaliers... Meanwhile, the wizard in his tower is happily forging away. :) It's why the dwarves were always looking to kill orcs. They couldn't be the iconic dwarf unless they really hit the level treadmill.

I don't usually like to say this, but what you're constructing there is a strawman (or so I am told). I think you're probably doing it accidently, as it sounds like you are not particularly familiar with AD&D.

Basically, it is for the same reason as you don't need skills at all. If you want your fighter to jump, he jumps. You want him to ride a horse, he rides. you want him to sneak, he sneaks. You want him to learn weaponsmithing, he learns weapon smithing. Sublimating these ideas into experience and levels as numerical expressions of skills is a flawed (in my opinion) approach. In D20, you end up with 20th Level characters who are 95% better at jumping than 1st level characters.

Now you may say, but he's 95% better at hitting stuff, why wouldn't he be 95% better at swimming? Fact is that first is also stupid, but the entire combat system was designed that way from the get go (well, not quite, but I'm not going to lecture on how OD&D worked). You don't need to apply the same logic to skills, though you can if you want.