Comment by happytoexplain

I see this sentence a lot:

"How can somebody who does X just do Y?", implying that Y is somehow bad or wrong in the context of X, or contrasts with the experience level implied by X.

Maybe it's true of the subject. Maybe they should have known better. But I think it's beneficial to take a step back and view it from the perspective of readers: Many people - even people familiar with X and Y - may have no idea why Y is bad in the given context, or, more relevantly, why this should be obvious, as you imply by using the word "just". I think there's a lot of benefit to be gained by trying to observe yourself, and notice when you are writing in this style, and add more context.