The chances that you are going to walk into the nearest shoe store and discover perfection in the first pair you approach are highly improbable. Even supposing you did, how would you know? Suppose they are the first pair of shoes you have ever had the luxury to experience. If you are inclined to enjoy the sensation of foot armor, then a life of barren feet will predispose you to exalt in even the shoddiest pair conceived.
To find the essential pair, you are going to have to try on a lot of shoes, and you will be visiting more than one shop. But here's the difference: this is an analogy about relationships. So, provided you're not polyamorous, you can only have one set of shoes, not a harem in the closet. This choice has to count.
Some of the shoes will have the perfect aesthetic. The moment you lay eyes on them, there will be an instant connection. You'll know that these shoes were made for you. Until you try them on, and then it's another story. You look gorgeous in them, but every step is torture.
Some will be hard pressed to capture your attention at all. You'll be thanking whatever karma fairies thrust them in front of you because they're not what you were looking for - with your eyes. You put them on, though, and it's all kinds of paradise. But then maybe you walk to the mirror and realize they have neon pink flamingo heads popping out of the toes. They repel you. Your relationship is half a lie. You can never love all of them. And you can only have one pair of shoes.
You'll try shoes that are too short, too large, too narrow in the toe, too pinched in the heel, too unsupported in the arch, too gaudy, too grisly, too high class, too unrefined, too casual, too high maintenance, and too many things to anticipate.
And then, through patience and diligence, one day you are going to find a pair that fits you in all the crucial aspects. A pair that compliments you so well it may almost have been tailor made, yet possesses sufficient novelty to hold your interest.
And now and then even this beloved pair will allow a rock to breach its barriers and, inadvertent or no, render you a wound. And eventually this pair will bear testament to your shared history together with a mounting collection of scuffs and wear. But the true test of their worth will be in how much (or little) these things matter to you against the measure of their merits.
Merits you will be sufficiently versed, by now, to appreciate.