It doesn't get any better as you get progressively higher end. Keeping with the chain analogy, if you start lowly, with the equivalent of a steel chain, if one link is weak, i.e. plastic, the chain can break.
However, as you get more and more refined, similar to a fine gold chain for jewelry, each link is so particular that one hears ever more distinction between components and the most minute changes can mean significant differences in sound, good or bad (at this point "It's all good," but one gets ever more picky as preferences escalate). That's when one realizes that you never get there, you never have the ultimate system.
Moral: Don't obsess too much about which is the weakest link. Go for symmetry and consistency in quality. Start at the wall (outlet), and work your way outward toward speakers.
However, as you get more and more refined, similar to a fine gold chain for jewelry, each link is so particular that one hears ever more distinction between components and the most minute changes can mean significant differences in sound, good or bad (at this point "It's all good," but one gets ever more picky as preferences escalate). That's when one realizes that you never get there, you never have the ultimate system.
Moral: Don't obsess too much about which is the weakest link. Go for symmetry and consistency in quality. Start at the wall (outlet), and work your way outward toward speakers.