West Point has a bunch of Officers and NCOs known as Tacs. They pretty much run the command structure of West Point and provide leadership, mentoring, advice, etc. to cadets.

The first line of Tacs is at the company level. Every company has a Tac Officer (Major or Captain) and a Tac NCO (Sgt. First Class).

There are Tacs going all the way up to the brigade level (Colonel and Sgt. Major) and they report to the Commandant (Brig. General).

Tac Officers and NCOs fill out their command structures.

Most cadet leadership positions are a semester long. Exceptions are the senior leadership positions, which are for the whole year.

The list of candidates for senior leadership positions is pretty small. They obviously have to be ranked well in their class in all 3 areas. But most importantly, they have to have done very well during their prior leadership positions (team leader as a yuk and squad leader/platoon sgt during cow summer and cow academic).

Cadets on the short list for leadership positions will be tested with senior summer assignments. Most 1st Captains were Commander of Beast 1 of 2 or CLDT. Most Regimental Commanders were Company Commanders during their summer assignment. There are definitely exceptions, but the paths are usually clear.

In short, the Tac teams know who is capable of leadership and they test/train them throughout their time at the academy.