Sometimes we get a question worded like "why do chefs do " when the OP really means "does doing X have any benefits".
I feel that the difference between the two is important and goes well beyond mere linguistic niceties. Equating both implies that chefs only do X when there is a clear culinary benefit in doing it, or that it is wrong to do X if there is no culinary benefit to X, which is a dangerously misleading assumption (and also undeservedly insulting to chefs).
Second-guessing people's motivations and reasons is not really constructive. Asking "why did the chef do X" when we really want to know "will I gain something if I do X myself" only invites speculation and in the worst case creates either irrelevant answers or myths.
My suggestion is to focus on what we can answer: the food technique itself. If somebody posts a quesiton of "why do chefs do X sometimes" should be edited into "What are the advantages and disadvantages of doing X". That way we have an interesting and answerable question.
This is of course a matter for a community decision, not something for a moderator (or some other single user) to simply proclaim, so I would very much like to see your thoughts, input, criticism and counter-suggestions.