"Why ...?" vs. "Why is it that ... ?"

Solution 1:

I see a subtle difference, which might be more obvious to anyone into Systems Thinking or NLP.

The first has a more passive meaning, in that it implies that a cause exists for everybody's desire to help, without specifying where that cause exists. The second implies that the cause lies with everybody.

You can see this more clearly if you use an example with something inanimate in it:

• Why is that the ball always comes through my window?
• Why does the ball always come through my window?

The ball doesn't come through the window of its own accord, of course. We would normally say something like, "Why do the kids next door always hit the ball through my window?" instead, because to assign the action to the ball, rather than the people hitting it, would be strange.

We might use "Why is it that...?" more often when the cause of an event is unclear. It can also help us look outside the immediate cause for external influences:

• Why do sparrows always fly into my window? (Stupid birds).

• Why is it that sparrows always fly into my window? (Because they can't see the glass).

Thank you for making me aware of this. Another linguistic Systems Thinking tool to add to my box.

Solution 2:

I think there is no difference except that the first sounds more emphasized. But there is no difference in meaning.

They are both asking for the reasons, although in a slightly different way.