For your clarified question specifically about ‘layers’ of flavors:
Yes, but not quite as often and maybe not significantly as you might think.
In the case of a spice mix placed onto a object, whatever is on the top is what’s going to hit your tongue first, and then after you chew you will get the flavors that have been added earlier. I don’t know that adding one spice than another will show much of a difference, but adding spices to a breading mix (either the flour, egg, or breadcrumb part) will typically be less noticeable than a similar amount sprinkled on as soon as you’re finished frying.
However, because it hasn’t been heated, the flavors going to be different (although in some cases the spices will burn if in the breadcrumb part)
There are literal ‘layer’ when you’re dealing with some confectionary (coating in chocolate, caramel, or hard sugar), but I don’t think this is what you’re talking about.
When rolling things in spices, it’s typical to mix everything together instead of rolling into multiple separate containers of spices for two reasons: (1) it’s a lot less work and (2) you get a more consistent ratio of spices. If you roll in one first, there maybe not be moisture left for the subsequent spices to stick well.
When dealing with things being stewed, braised, or boiled, you get a similar issue… the first flavoring may absorb better than the subsequent flavorings, so you may need to add them in a specific order or all at once to get the proper balance. Chef Saito on NHK’s “Cooking with the Chef” had a recipe where be added sugar first, then salt a minute or so later so the larger compound had a better chance to absorb.
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But for much of this, I would suggest making two batches, try taking whatever shortcuts you want on one of them while following the recipe on the other, then decide for yourself if the extra work is worth it. It’s possible that your tastes might lean towards the easier version