Presumably because a lot of people wanted to buy a computer in, say, January but decided to hold out for the next refresh, which was at the time expected to happen in March or so. Unfortunately, that new model was seven months overdue (http://buyersguide.macrumors.com/#Retina_MacBook_Pro) and yielded disappointment over the price (I recall hearing that the price of the base model went up by about $200, but I can't find a citation for this) and the suitability of the system for their work (e.g. replacing the tactile escape key with something that seems like "a useless gimmick").

So they have a computer they wanted to replace ten months ago (or indeed any time since then) and no good options from Apple. And before you suggest they just buy a previous-generation MacBook Pro; do you really think the best thing to do today is to buy a two year old computer?