Before coming to Japan the first time, I had a theory about sushi. My theory was that the sushi in Japan would be better than the sushi at home, but the same in the way that all sushi is the same — fish on rice, basic technique, varying quality of ingredients. My theory was wrong. It's not just better. It's a different thing.
The difference starts with the rice. Sushi rice in Japan is warm — body temperature, roughly — which sounds like a small detail but changes the texture and the way it holds together entirely. The seasoning is lighter. The compression is lighter. The fish sits on top of something that yields slightly rather than a block. This sounds like it shouldn't matter. It matters.
The tuna — maguro — is the test I run everywhere. In Japan, even at mid-range places, the colour is a deep, clean red with no brown at the edges, the texture is dense without being chewy, and the flavour has almost no fishiness to it. Two pieces arrive on a plate and you eat them immediately. That's the other thing: the timing. Sushi is served to be eaten now, not in ten minutes.
Uni — sea urchin — is the one that divides people. The version you get at home, if you get it at all, often has a faint bitterness and a texture that takes some convincing. Fresh Japanese uni has neither of those problems. It's sweet, clean, and almost creamy. Served on cucumber with a little ikura (salmon roe) on top, it's briny and rich and gone in a second. I've watched people who claimed to dislike uni eat three of these in a row and say nothing.
The crab nigiri is the one that feels most decadent. Snow crab legs draped over rice, the meat pulled into loose strands that look impractical to eat and aren't. The nori holds it together just enough. You pick it up, it holds, you eat it in two bites. The sweetness of the crab is completely unmuddied — no heavy sauce, no dressing, nothing added that would get in the way.
We went to a kaiten-zushi — conveyor belt sushi — not the cheapest one and not an omakase counter. The middle tier, the kind of place that's busy at lunch on a Tuesday with families and office workers, not tourists making a special occasion of it. The quality was, by any reasonable standard at home, exceptional. In Japan it's just Tuesday lunch.
That's the part that's hardest to explain. The baseline is so high that what we'd consider a genuinely special meal is just a normal option. There's no trick to finding good sushi in Japan. You just go to a sushi restaurant.