One thing that always pissed me off was how necessary Call of Duty's ADS is.
Like, you'll literally watch your bullets fly out of your gun's barrel sideways with hip-firing. Coupled with an already slow walking speed, engagements will most likely involve you standing still while firing, and any sort of movement will usually end up getting you killed (especially since bullets penetrate fucking EVERYTHING) since sprinting is the only way to effectively get away from a threat, but while sprinting you can't shoot or aim at all.
It's so conducive to camping, it's insane. And at the same time, I still loved it.
Weird.