What things make blepharitis more likely?

Heat, age, hygiene. Blepharitis gets worse when its hotter, as people age and as people fail to keep their eyelids clean. Regular lid hygiene (instructed by your doctor) with occaisional topical antibiotics controls it. Bad cases and patients with rosacea (see your doctor for this diagnosis) are often given systemic antibiotics (pills you take by mouth) in addition to topical. Its never cured-its controlled!
Skin problems. Blepharitis is a chronic inflammation of the eyelid margin. It can cause redness, irritation, burning and dryness. Risk factors include acne rosacea, seborrheic dermatitis, dandruff, diabetes, dry eye and age. Blepharitis can be managed in most patients, visit your eye doctor to formulate a treatment plan.
Blepharitis is like. Blepharitis is like white hair. It just happens. The skin renews itself about every 72 hrs. The skin of the lids is the thinnest. Dead surface skin cells form keratin. In blepharitis the dead skin wraps around the base of the eyelashes, creating an environment for bacteria to "nest" in this collarettes. Bacteria multiply and cause the symptoms of itching redness. Wash your eyes with baby shampoo.
Youth. Blepharitis is more common in young people. It bears some similarity to dandruff. There is a shedding of surface cells with a dried fatty overlay under which hid surface bacteria the products of which lead to redness and itching. You need to clean your lids of the fatty deposits and then apply a comination antibiotic/steroid that you can get from your ophthalmologist.