In your opinion what are the reasons that let someone start dumping his bitcoins and walk away ?
I personally (and this is just my opinion) that it's more panic then simply his need of money or something else , as we saw on the BitcoinXT last time , people started to panic and simply sold their bitcoins and that caused a drop in the price .
True. Newbies have somewhat higher (unrealistic) expectations regarding the profit making fundamentals and this is the main reason that they tend to get frustrated of waiting and dump their Bitcoins. What they need to understand is that the BTC market works like any other market. The price is bound to rise when more people want in on the BTC market. A little bit of patience and analysis of the recent market trends can see them making substantial profit.
But in fairness with the current situation today unlike the past XT drama that many dump their coins, volumes of buy rate in the past days are rising near the average of sell rate. By looking at the daily chart, you will see that graph almost the same everyday of pump and dump rate.