The first 15 minutes of trading are usually the most volatile time to trade, and I think a lot of amateurs are getting emotionally drawn to the stock and placing bids much higher above the previous day's close (also known as gapping up)....when the stock gaps, it has to touch back to the previous day's price before moving north (as a rule of thumb, it's about 98% accurate).
It bothers me to see high bids before the market opens, because I know the stock is going back to neutral before going back up. Then the early buyers get scared and sell, so this whole snowball effect gets created and the very clever and smart traders will wait it out and buy the stock at rock bottom for the day.