5. Impatience and Lack of Time
Never reapply mascara if the first layer is not yet dry enough. Take some time, wait a bit, and be patient. When the first coat is dry, add another one and do not forget to separate your eyelashes from each other by wiggling the brush along. The brush is supposed to glide along without sticking.
Are there any other reasons why mascara may clump? If so, let us know!