Nine women can't make a baby in one month.
If Apple has to "borrow" developers from one project to finish another, then put them back to finish the first one, then I think its logical that if they had a full staff for both projects, they would both be done on time instead.
You can't say that taking iOS developers away from iOS and to work on Mac OS X has no negative impact on the timeline of iOS development. Clearly, those developers are missed and features get heavily delayed. Something that wouldn't happen if both teams had a full staff.
In fact, if both had a full staff, then Mavericks would've been a more major update (which it wasn't because developers from there had to be "borrowed" to work on iOS, and iOS would this year not have features fall through the crack due to "borrowing" to work on Mac OS.
In fact, it looks like if they just gave the order to HR to make sure there's enough developers for all their endeavors Apple would be 2+ years ahead, which would be great for their competitive advantage.
Updates going forward would be consistent, more polished, and cover more ground.
I have my own business and I know how product development and teams work. My organization, as well as many others, is hampered by the cost of expansion (limited office space, equipment, etc. would mean big investments needed that we don't have the cash flow for -- something a giant stockpile of cash clearly solves) as well as the fact that top management must oversee many things because I cant afford to hire 6 figure or higher managers to take my place on existing tasks.
Apple has no resource problem. They are sitting on $117 billion (or more) in CASH, while their development teams are suffering delays, working overtime, and having to borrow staff from each other at the expense of features and release days that get pushed back.
Its illogical.
I am not saying they should balloon and double or triple in size to where they can't control quality anymore (cant have too many new people or else assimilation into the culture is tough), but surely hiring enough developers so that the iOS and Mac OS teams are fully staffed, FULL TIME, would really help things out.
I figure an organization can add 10% to 20% more staff in short order without suffering in its culture if they have strong leadership.