A lot of champions base their whole game around pulling half guard and then coming up for a sweep.
Why is this?
I believe this is because the half guard is a very versatile position...
You can sweep, submit, and transfer into other guards and positions with ease!
Because of this, it's very rare to even see people playing a closed guard now a days.
Most people stick to just one half guard system like deep half guard, under hook Lucas Leite, Knee shield half guard etc...