My Co-Worker is Holding This Stock? Should He Hold or Sell???

I was talking to my coworker, and he is into stocks. He invested money and was up over 6k. He then gave it all back holding. He is now only up 600 bucks. I told him I would take profit, and buy the dip later. I told him to get out based on the pattern forming. I also told him not to listen to me because it was his money. Looking at this stock, and everything going on in the market, I would definitely sell. I am simply a grasshopper lol. I need some advice from some of the pros. What do you think he should do? Sell or Hold? I say sell, and buy at support.