Lightning strikes deal 10 damages [5 hearts] to players [I was inside my cobble roofed house when it struck, the roof is 3 block tall (can fit Endermen in the house)]. No fire created [maybe they are on the roof?!]

Another lightning stuck a horse, created a fire under it which wasn't put out by the rain and kept on burning said horse. The horse "flashed" many times and died. Horses have at least 15 points of HP (7,5 hearts). If the (bugged) lightning strike deal 10 dmg + 4 dmg from fire then why did it die????