Other then the fan and harddrive, the MacBook does NOT have much in the way of moving parts. Unfortunately, even in its an aluminum enclosure, the parts are small and easy to break if dropped.
You missed quite a lot. Hinges. Trackpad (not a moving part per-se, but the coating can come off). Trackpad clicky button. Keyboard. Power button. All the individual keys.
On a desktop, replacing the keyboard or mouse is a 5 second, $10 job. On a macbook with no warranty... replacing the keyboard or trackpad... hmmm hope you just got paid - could cost $200 or more.
Problems could come just from crumbs jamming keys or the click button, or liquid spills.
However, I am on the fence about applecare. I plan on buying a refurb MacBook soon, and $250 is a lot of dough
eBay. (with usual warnings)
most computers either fail right away or last a few good years. If the comp doesn't fail in the first year, then it is likely to last 3 years.
Desktops last. The expensive bits (monitor, CPU etc) are either up in the air or well hidden away. Most other bits (mouse etc) are easily replaceable. In extremis, I can replace a desktop motherboard for £40 labour plus the £40 cost of a new mobo.
Laptops don't. They suffer more wear and tear from daily use. People here have been quoted $1000 for replacement logic boards (apple mobos). Laptops have power lead and USB stuff (external mouse, drives, keyboard, etc) plugged in and unplugged almost every day. (desktops less often) It's more wear on the ports on the mobo.
Also laptop mobos have greater thermal stress, as there's less cooling and stuff is packed more tightly than on a desktop mobo. They get flexed when people pick up the laptop by the corner (as does the LCD too). All that just adds up to a shorter life.
My old POS Acer laptop is 4 years old, but it is so big and heavy, it has mostly been a desktop machine. It has had no real serious issues, but the battery blows at this point and a blue line appears and disappears on the screen sometimes. I hate moving it around cuz the battery will shift out of place and the whole thing shuts off or the blue line appears
As you say, your laptop was mostly used on desktop only, but you've got battery problems, LCD problems, and hinge problems. Some of that probably started showing up before the end of the 3rd year.
I have to keep fiddling with the hinge in order to get it disappear again.
How did you forget the hinge in your list of moving parts above, when you're having hinge problems yourself? A lot of important cables go through the hinge (LCD, Wifi, webcam, etc) so hinge problems can create a lot of knock-on problems.
Hope I've made my point.
