Jack, it happens most days but some people still did not notice...

Jack, it happens most days but some people still did not notice the trick & fell into the trap day after day.
Few minutes before close, someone will sell down the stock ( probably selling to each other) to tick the SP down.
Then at close, someone will bid the SP up, just enough shares to bid at higher price , making the foolish one to compete for the bid & lower their ask price. With few seconds all bid at higher price pulled & the innocent & vaive got caught again & again.