Roast level can help a buyer describe a preferred direction: brighter and more origin-focused, balanced across several attributes, or more obviously roasted and substantial. These are broad tendencies. Different roasters apply light, medium and dark labels differently, and the underlying coffee still matters. The source follows a comparison from floral and lemon-like impressions towards honeyed or more roasted notes, illustrating why roast choice changes the buying decision.
Consider how the drink will be served. A coffee that is pleasing as a small black cup may behave differently in a large milk drink or after substantial dilution over ice. That does not make one roast level universally correct for a method; it makes the intended strength and balance relevant.
Try a manageable bag and keep the dose and water quantity recorded. Adjust the preparation before deciding that the roast category is unsuitable. Clear descriptions and a repeatable cup are more informative than choosing solely by bean colour or assuming a darker roast must contain more caffeine per serving.

The conversation
A good question can make a better brew.