Oh give me a break, Apple products are nowhere near perfection. They do plenty right, but plenty of their stuff is awful (just like every other company out there). Finder is awful. The calendar and notes app are awful. One of the ugliest things about Apple is the constant insistence by users that everything Apple does is perfection.
I didn't say they're perfect or anywhere near perfection. I could go on at length about the myriad things that annoy me: Finder, HFS, software update crammed in the App Store, iOS lockdown.
All I did say is that they absolutely do _care_ about what's below the surface. Parts that a fraction of a fraction of folks will ever see are given loving attention far beyond the norm. Do most or any other manufacturers color coordinate battery warning labels, PCBs, etc., down to the cm^2 headphone jack?
But … it took 5+ years not to freeze the UI if the network dropped a packet and lookupd ran out of threads. This was much worse if you used a network authentication service like LDAP – I submitted the same libldap client patches which I sent upstream to the OSS devs (http://chris.improbable.org/2008/03/15/borrowing-from-the-fu...) – but this and NFS client kernel deadlocks and other problems (they accidentally broke Unix permissions for a few releases in the 10.4 days) were generally either ignored or answered with something like “How many Macs does this problem prevent you from buying?” (NOT a joke).
iOS's WiFi still hasn't fixed the basic usability bugs I reported against 1.0 (simple things like “Don't capture the UI until the hotspot page has actually loaded” or “Don't nag me asking to reconnect to a marginal network I already requested you connect to”).
iOS autocomplete remains an embarrassment, frequently turning correct words into nonsense or failing to handle minor inconsistencies in input which didn't produce a valid word.
iOS backups don't backup the stuff you care about like passwords or settings but do backup things you can trivially re-download from the store like apps. This is not in any way documented and the backup status will simply claim the backup was successful without mentioning that it includes almost nothing important.
FileVault had data-loss bugs for multiple releases until v2 was released. Time Machine still doesn't check data integrity and the remaining users complain about weird UI bugs, performance impact, hangs & data loss, etc. Nobody at Apple appears to care.
iCloud sync is a disaster with uncontrollable delays and hangs (e.g. http://createlivelove.com/246). There's no sign of anyone at Apple caring since it hasn't impacted iPhone/iPad sales.
To reiterate: Apple doesn't obsess about quality unless it's needed to get people to buy the device.