If you have OCD and/or fashion sense, you would know that gold and silver don't go together. And if they were going to make some of them gold, that one random pin is really frustrating.
Gold and silver definitely go together what the hell?

And a pattern of four with three repetitions and one variation is sensible and balanced and we see it in all types of art (especially music). It's certainly more interesting than having everything perfectly symmetrical and 'square'.