Why does salt taste different in different dishes?

Question

If I salt tomato, potato and pasta, their tastes change in completely different ways to me. Why is this? Had I put oregano on them, they'd all taste like oregano.

Update: The question is not "is it so?" but "why is it so?"

Answer

Salt is completely water soluble, unlike only trace amount of what is in oregano. That being the case, it will completely saturate anything that is wet, therefore it can completely consume and pair with every bite, whereas oregano remains in chunks and can be distinctly tasted alone.

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