Some interesting stuff there. I think you could also frame it as a explore vs exploit problem. If we assume there is a successive series of partners you could meet but only in sequence and you choose whether to "attempt to exploit, i.e. form a relationship" or pass and continue to explore. At which point should you commit such that it maximizes the expected gain (marginalizing over your lifespan)? It's like RL game e…
What you describe is called the "secretary problem", among other names https://en.wikipedia.org/wiki/Secretary_problem
Optimality breaks down when humans get involved. Because what most humans need is to believe they did a good job picking, which is quite a bit different. If the best solution falls into your lap you may continue spending energy on that decision forever, and that longing for what might have been is a big opportunity cost (which is magnified if your partner ever finds out about it). We have this sort of intuition that we have to put a bit of sweat equity into a decision before it feels good. Which may relate to the somewhat debunked theory of 'ego exhaustion'.
You may know what fridge you want but you have to keep showing options to your spouse because they aren't okay with the decision yet, and if you rush it then you'll regret it. You can spend that energy now, or you can make emotional interest payments for the life of the fridge. At work you sometimes have to do the wrong thing so that people get why the more expensive option makes sense.
What my friend was doing and what I see other people do, including myself, is make a list of targets of opportunity. 5% of the options are acceptable and I will stop when I get access to the first one in that category, be it a fridge, an islander, or a partner. This person is smart, funny, likes cats, and your family adores them, and you have chemistry so why not. You feel good with your decision, or at least you do at the time. You might still leave them six years later because it turns out those other things you didn't like overshadowed everything else, once you had to live in the same house. How many other potential matches went away during that time?