Here’s how I see it FWIW.
I spend 20-50 dollars on a lot of things that bring me joy often without thinking twice. A meal, movie tickets, a bottle of Bourbon, etc. Many of these things are short lived. I don’t collect them or use them over and over but they are fun while I am doing or consuming them. Sometimes those things also turn out to be duds, i.e. a bad movie or meal.
So when I make a purchase of a knife that’s a good deal, even if it is not a brand that I “like” and even if it does not wind up being used, it often brings me pleasure at least for a few hours or a day or two.
That’s not a lot of money to spend compared to other things I spend money on for a couple hours of enjoyment.
Even if I hate the knife after a few hours there is almost always some period of excitement, fun, anticipation, interest, etc that usually justifies the cost for me.
And, I always learn something from the knife that I may look for or avoid in another knife.
And finally, knives are pretty easy to move along. Sell them, trade them, or check it the PIF thread here for the opportunity to make your “investment” morph into something you might just use.