Usually the "notes of" doesn't mean added flavorings, it's just a taste profile similar to describing wines or perfumes.

Apparently a trained palette can distinguish different notes, but that requires trying each one in isolation which is difficult for the average person to do.

For me I can only really identify bitterness, acidity, body, and strength. That's all a casual drinker really needs in order to describe what they like.

• The bitterness is self-explanatory, and depends on the beans, how they're roasted, how they're brewed, etc.
• The acidity is the brightness that you can taste in something like a light roast. Try it side-by-side with a dark roast to taste the difference.
• Body is the thickness of the mouthfeel. The best way to describe it is like drinking whole milk vs. skim milk. Light roasts usually have a lighter body, like water. Dark roasts have a heavier body, not quite like whole milk but maybe skim.
• And strength is self-explanatory. Light roasts are technically stronger because some of the caffeine breaks down when heated (green coffee, sometimes called golden coffee, is the strongest because it isn't roasted), but I find the difference is negligible. The main factors for determining strength seems to be how it's ground and how it's brewed.
  • The finer it's ground, the more surface area so the stronger the infusion, that's why espressos and turkish coffee are so strong (also because they might blend some robustica in with their arabica, which makes it more bitter but also has more caffeine)
  • Also higher grounds::water ratios means there's more caffeine, but too high and it gets undrinkably bitter with an extremely thick body (sometimes called "motor oil" for this reason)

That all being said, some roasters do add artificial flavor directly to their beans, but usually those are called "flavored," not "notes of"/"hints of".

And yeah, skip me with those flavored syrups. If I want something fancy I'll add real cocoa or some herbs or something, but that's a rare inkling for me and those syrups are just kinda gross.