I think it is the combination of the flavour and the magical effect we feel when savoring that delicious nectar that makes us stay attached to a cup of coffee every day. It is not only because of the taste but also because of what we feel when that wonderful smell and taste permeates our body and fills us with a unique and indescribable energy that makes us love it more and more every day.
This can be verified when we have a very stressful day, it is enough to drink a cup of our favorite coffee and at once we feel that our body is reactivated, it is as if our batteries were recharged and that makes us lift our spirits.