yeah. My Mac Air is a custom build - but getting to it was a conceptually simple process. Mac Pro/iMac/Mac Mini/Macbook Pro/Mac Air? Low-end Air or high-end Air? Want to customize that?

Apple's got about fourteen separate computers they'll sell you (plus tablets/phones), but that's folded away behind six distinct products that come in two or three stock configurations. If you had to choose between those fourteen things up front it'd be a lot more conceptually complicated.