I cannot find myself a good lip shade

Honestly, I can't figure out what I'm doing wrong in trying to find my perfect lip shade. I've got dusky/wheatish skin, and yet, despite buying no less than 20 lip products, including balms, serums, and matte lipstick, I haven't been able to find any shade that would suit me.

I can't decide whether some colors appear too washed-out (mostly lighter nudes and pinks), or whether the problem lies in my face shape or whatever because, even though I've tried a variety of shades, the results still aren't satisfying.

In fact, I suspect that it may be my pigmented lips that cause the problem since not all shades work well. Besides, there is always the issue of finishing because, for example, matte shades can look too pale or even faded on me, while gloss finishes seem more natural, but still imperfect.

So what is it that I'm doing wrong, or am I simply missing a simple guideline that everyone else seems to know about? How do I actually go about figuring out what suits me?