It's called "day trading" people. The last 15/20 minutes before the market closes is when you make "that" decision... do I hold or sell.
If you can make 5% to 8% per day on a stock...why not sell?! Not a bad return on a yearly basis. Heck! Not a bad return for each week you trade.
Not sure WHY you are wondering WHO is selling? Does it really matter WHO is selling?!! IF you KNEW who was selling, could YOU change things????????!!!! NOPE!!!!!!!!
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