The reason: Avoid applying liquid foundation with your fingers as that can cause bacteria to build up quicker; brushes and sponges, when washed regularly, can help your liquid foundations last a year. If you use foundation out of a squeeze tube or bottle with a pump, application style doesn't matter as much. Store in a cool, dry place away from direct sunlight and close the lid tightly to keep it from bacteria and drying out. In general, color and consistency will turn after a year.
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