I genuinely believe that roughly 10% of most companies are ineffective employees, whether via being a dumbass or just not caring (valid or not).

fuck, I'm seeing it happen as my own company grows from very small to medium small (a few dozen people). I swear some of my new coworkers are just AI with the way they lie to your face, you point it out, and then they immediately agree with you that yes what they said was incorrect.