Most buyers choose their colour under showroom lights, and most second thoughts start in a car park on a grey morning (sample note).
Take the chip outside. Look at it in shade as well as in sun, and hold it next to the leather swatch you are thinking of: a warm hide can make a cool blue look green.
Metallics hide small marks better than solids, and dark solids show every swirl from the car wash. If you are between two colours, ask to see both on a car; most colours in our book are on the floor or in the workshop.