In art, the defense of this theory is that "only God is perfect,"
Well, there you have it, around here at least.....so many consider you God that you must design the perfect course, every time!
Seriously, your last answer, and a few others suggesting a round of golf is a collection of holes, so you must judge them partially in the context of the others that surround it, hit the nail on the head. If perfectly placed, a "breather hole" is a great thing, a purpose built "weak hole" by someone's definition.
For that matter, a great hole, which happens to be the third long par 4 in a row, or the third hole in a row to require a, say, fade may no longer be considered a great hole in the context of playing a round of golf, even if each would be considered for a book like Golf's "500 Greatest Holes." A course with 18 great holes would probably be a bad course, no?
I recall seeing some of Pete Dye's mid career work, like PGA West. Every hole was built to be spectacular to look at. The thing is, if every hole is a signature hole, then its likely none are. If every hole is visually spectacular, they tend to blend together as much as 18 mundane holes.
If nothing else, the way golfers love to rank everything, sooner or later, for any course, holes will sort themselves out in an (often) generally agreed upon ranking, 1 to 18, no? Then, the lowest ranked hole(s) will be considered weak.
As others have noted, if each hole has a purpose, distinct from other holes, it doesn't have to be a weak hole. Now, the challenge presented, let's say placing a short iron in a specific part of a large green, might not be as difficult as placing a long iron on a small green, but it is a unique challenge worthy of putting somewhere in the round, no?
What about figuring out a level putt, on a course full of contoured greens? Is that weak in context of playing the round? It may be weak in context of award winning golf photos, but then there are many lenses from which different folks judge courses. One man's trash is another's treasure, and all that.