the profit is fixed, equals to the premium of the put option, and the risk is limited , the upside loss comes when the price of underlying assets fall to 0.
Sell Put就是很简单的Long Delta Short Vega,俗语叫做看不跌。一般来说在市场触底的时候你可以考虑sell put,另一种情况是在超卖的市场中,例如金融危机,恐慌心理使得put供不应求导致put的IV飙升大幅超越正常值,这时卖出put可以赚取“市场定价错误”的收益,但也有可能是火中取栗,sometimes market is correct,but sometimes wrong