A good foundation will be blendable so that it doesn’t look thicker in one area of your face than in another. It will provide coverage that is smoothing and able to hide small blemishes in your complexion. It should wear well throughout the day and not get cakey or drippy at any point. A good foundation is buildable, meaning that after you have applied some and you need to add more in certain areas (or all over), it won’t have any texture problems. Lastly, it should dry to a nice finish and won’t look uneven.