1) Fight against vision threatening diseases: diabetes, cataracts, corneal degenerative diseases, macular degeneration, idiopathic and pathologic choroidal neovascular membranes, glaucoma, sarcoid, GCA, etc...
2) Identify and treat diseases that detroy vision and life: retinoblastoma, melanoma, ocular tumors, collagen/vascular diseases, aneurysms, endophthalmitis, etc...
3) Save vision by repairing ocular trauma: 10% of all trauma involve the eyes even though the eyes are less than 0.5% of the total body's surface area. Although we may not get called often, there are orbital traumas during the night.
4) Opportunity to work with patients who are completely grateful for the care they receive. Unless you have experienced the possibility of losing vision or an eye, you'll likely not appreciate the medical care provided by ophthalmologists and optometry.
All of the above with good income and lifestyle!