-> there is a limited amount of good engineers. You can't hire every guy who claims to be an engineer because he did a webpage once.
-> 9 Women can't make a baby in one month. Same with software.
Some problems can't be parallelized and needs to be implemented serial.
-> it doesn't make sense to hire more people if you don't need them unless you have a crunch time. In most cases it is better just to move the release.
Especially apple says "its done when its done".
1. There are plenty of excellent engineers, especially in today's market, in need of work. Hiring more to address the lack of engineers thus pulling them off development for iOS work does hinder OS X progress. It already has with Leopard in 2007 as it was delayed twice, and is now happening again.
Apple announces Leopard delays due to the iPhone
In a way though, I'm not surprised either, as a number of Mac OS X developers have expressed disbelief that Apple was going to hit a June release with Leopard in its currently buggy and fairly unfinished state.
2. Bad analogy as 9 engineers can positively impact development while releasing the update on time. This is not a "too many cooks in the kitchen" scenario but rather more objective heads involved notice bugs/issues other engineers miss as due to stress, lack of support especially when constant work on the same thing produces tunnel vision. Objectivity leads to better results.
3. Finder HFS+ needs updating. As ZFS+ once existed in Leopard beta's is no longer an option due to licensing issues and not being a proper OS X FS replacement, at least bring requested features third party app's address (XtraFinder is a free app with great Finder features). Tabbed browsing, dual sidebars, Cut/Paste/Move to, improved network protocols and stability, and finally fix customized view options that don't fully apple across selected folders and subfolders, etc.
4. Memory Management has been awful since 10.7, with welcomed improvements in 10.8 yet still needs addressing (I shake my head when glancing at console reports on my Mac Pro, Mac Mini, MacBook Air and iMac - all current gen with clean installs off 10.8's ESD dmg via USB).
5. OpenGL Core support (it's embarrassing only 4.1 shading is supported while Windows blows OS X out of the water, requiring many to boot into Windows due to OS X lacking support)
6. Wi-Fi has been unstable for many since 10.7. A Google search or quick glance at the OS X development forums will show just how prevalent problematic wireless/Airport has been for some time. I have used Snow Leopard on the same systems with no WiFi issues, yet both my 2.4 and 5GHz Airport Extreme bandwidths slowly lose signal strength on all my devices no matter the location, channels used, etc. Many of us have opened and acknowledged bugs since 10.7.
7. iCloud support with document syncing for those of us who use our devices for work, not games and movies. Adding back Keychain and Dock syncing across Mac's would be much welcomed, as well as a working replacement for the ill-fated iDisk.
8. iWork 09 and iLife 11, the year release dates state enough. The main updates have been for iOS support. Where is iWork '10, '11, heck, even '12?
9. Pro-Apps - After the Final Cut Pro X fiasco many jumped ship to Avid and Adobe's CS releases impressed many and pulled in the market Apple dropped (the latest finally brought back much needed features). Lightroom 4 is running circles around the dated Aperture 3.0 (which received updates for social networking as us photographers get so much business from Facebook, and a few RAW camera updates yet still lacks support for many).
10. OS X Server since Lion has been stripped of tools needed in order to appeal to the mass consumer market. Dozens of threads and articles address the removal of crucial components with OS X 10.8 Server.
Server, simplified: A power user’s guide to OS X Server
When Apple discontinued the Xserve at the beginning of 2011, it sent a message: it was abandoning whatever ambitions it had harbored for the enterprise market, starting with the hardware. That message was restated emphatically when Lion Server came out later that year sporting a consumer-friendly price point and the dumbed-down Server.app in lieu of the administration tools OS X Server had been using for its first decade.
11. Quicktime - it's sad when a free app such as VLC outperforms and supports more codecs than Apple's media foundation. There's no reason for an outdated framework important to OS X.
12. iPhoto for iOS is a better app than iPhoto for OS X as many attest. It's embarrassing as the main conduit for OS X photo management. Apple removed the ability to retrieve deleted photo's in iPhoto 9+ via "Time Machine". Yes, you must empty iPhoto's trash, however that doesn't excuse having to restore an entire iPhoto library if you or someone else inadvertently deletes a needed picture.
When using iPhoto ’11 (version 9.2 or later) and Time Machine with OS X Lion 10.7.2 (or later), iPhoto no longer has the Browse Backups option. This means that instead of restoring specific photos within your iPhoto Library, you must restore your entire iPhoto Library.
Source:
iPhoto '11: Restoring from Time Machine with iPhoto '11 (9.2 or later) and OS X Lion 10.7.2 (or later)
13. Mail - Improve rules management, handling multiple accounts, improve enterprise support, update layout. Outlook may be a hot mess, at least they offer full features that OS X Mail lacks.
14. App consolidation - Notes, Reminders, Tasks - too many apps that essentially do the same thing. Even iTunes has become bloated, handling too much media as the main conduit for device syncing and media management. No support for NAS's, open source codecs aside from a small selection, and horrible memory management.
All these issues have been acknowledged and discussed for quite some time. Some are intentional as Apple shifts focus, most simply lack the support necessary for resolutions. Apple is more focused on iOS, I don't see any iOS engineers being pulled into OS X development. There's no logical excuse to not employ more engineers as the company has grown in incredible strides over recent years. With growth comes responsibility to the consumers who own the products, if the company is unwilling to use a small portion of those billions in cash to improve their engineering teams this cycle will only worsen.