Why does my foundation look patchy even with primer?

Could it be that the primer you're using isn't the right one for your foundation? Or perhaps the primer isn't being applied evenly, leading to some areas looking smoother than others? It's also possible that your foundation isn't being blended properly, or that it's not the right shade for your skin tone. Additionally, skin conditions like dryness or oiliness can also affect how foundation looks on the skin. Have you tried using a different primer or foundation, or experimenting with different application techniques?