Keep asking why to get at all of the underlying assumptions.

When acting in the role of a business analyst and gathering requirements for the next great feature, it is crucial to understand not only the request, but all of the underlying assumptions and motivations that went into the request. This is because it is quite possible that the business is asking for the wrong thing in the mistaken hope of getting what they want.
For example, maybe they want to increase client conversions on an application form, so they want all of the fields to fit on one page. Then further think that the page needs to have three columns to fit all of the fields on one screen. Of course to accomplish this, they want to use a tinier font.
So a request comes in to use a tiny font and three columns. The developers are puzzled by this as they believe this will hurt conversions. A bad business analyst will say, “Well, that’s the business requirement, go implement it. We need to give them what they want.” The developers do their job and switch the layout to three columns and a tiny font and it’s a disaster.
A better business analyst will look at the tiny font request and ask “Why?” To fit in the three columns, they reply. “Well, why do you want to do that?” So a one-page form will fit on a screen. “Why does it need to fit on a screen? All browsers support scrolling.” Because they don’t want users to have to scroll, they say. “Why not have separate pages like before?” Because we want to increase conversions by avoiding page transitions.
Now the analyst can keep asking questions, learning about the desire to increase sales and the concerns about losing sales when people abandon applications in the middle of the process.
Through serious conversation the business can learn that having tiny font would not improve conversions. This might lead to better research towards what would actually improve conversions.
So keep on digging and asking why.